Danielle Rae Daniel 1 * , Tara Rava Zolnikov 2

AM J QUALITATIVE RES, Volume 7, Issue 4, pp. 1-32

https://doi.org/10.29333/ajqr/13596

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Posttraumatic stress disorder (PTSD) is a multi-faceted, symptomatic mental health diagnosis often accompanied with various physical and psychological comorbidities.  The complexity of this diagnosis makes treatment difficult, thereby suggesting that all options, including alternative approaches to care, should be explored. Aromatherapy from plant essential oils is an increasingly utilized integrative health modality. Essential oils are lipophilic, volatile aromatic metabolites in plants consisting of various natural chemical constituents that permeate the blood stream and influence neurobiological responses. This qualitative phenomenological study sought to understand the impact of aromatherapy from Bergamot essential oil on managing PTSD symptomology. A two-week pilot study was conducted consisting of 12 first responder, medical, firefighter and military men and women presenting with symptoms of PTSD in San Diego, California. Data collected from the interviews identified that the bergamot essential oil produced a calming effect, improved sleep, reduced anxiety, increased positive mood, enhanced concentration and reduced avoidance behavior. Participants in the research study reported that aromatherapy of bergamot essential oil helped mitigate certain symptoms of PTSD from the symptom clusters of arousal, negative mood, and avoidance behavior. This modality could help practitioners and treatment clinics facilitate an adaptive recovery, by providing a calm and safe atmosphere to engage with clients to execute trauma focused therapy more effectively.   Aromatherapy provides a non-invasive and promising modality that would best serve the mental health field for practitioners and their overseeing organizations to further research, educate and implement this therapy in facilitating an adaptive recovery and management of PTSD symptoms.

Keywords: PTSD, mental health, aromatherapy, essential oils, complementary alternative medicine.

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  • Published: 26 July 2022

Effectiveness of aromatherapy for prevention or treatment of disease, medical or preclinical conditions, and injury: protocol for a systematic review and meta-analysis

  • Sue E. Brennan   ORCID: orcid.org/0000-0003-1789-8809 1 ,
  • Steve McDonald 1 ,
  • Melissa Murano 1 &
  • Joanne E. McKenzie 1  

Systematic Reviews volume  11 , Article number:  148 ( 2022 ) Cite this article

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Aromatherapy — the therapeutic use of essential oils from plants (flowers, herbs or trees) to treat ill health and promote physical, emotional and spiritual well-being — is one of the most widely used natural therapies reported by consumers in Western countries. The Australian Government Department of Health (via the National Health and Medical Research Council) has commissioned a suite of independent evidence evaluations to inform the 2019-20 Review of the Australian Government Rebate on Private Health Insurance for Natural Therapies. This protocol is for one of the evaluations: a systematic review that aims to examine the effectiveness of aromatherapy in preventing and/or treating injury, disease, medical conditions or preclinical conditions.

Eligibility criteria : randomised trials comparing (1) aromatherapy (delivered by any mode) to no aromatherapy (inactive controls), (2) aromatherapy (delivered by massage) to massage alone or (3) aromatherapy to ‘gold standard’ treatments. Populations : any condition, pre-condition, injury or risk factor (excluding healthy participants without clearly identified risk factors). Outcomes : any for which aromatherapy is indicated.

Searches : Cochrane Central Register of Controlled Trials (CENTRAL), with a supplementary search of PubMed (covering a 6-month lag period for processing records in CENTRAL and records not indexed in MEDLINE), AMED and Emcare. No date, language or geographic limitations will be applied.

Data and analysis : screening by two authors, independently (records indexed by Aromatherapy or Oils volatile or aromatherapy in title; all full text) or one author (remaining records) with second author until 80% agreement. Data extraction and risk of bias assessment (ROB 2.0) will be piloted by three authors, then completed by a single author and checked by a second. Comparisons will be based on broad outcome categories (e.g. pain, emotional functioning, sleep disruption) stratified by population subgroups (e.g. chronic pain conditions, cancer, dementia) as defined in the analytic framework for the review. Meta-analysis or other synthesis methods will be used to combine results across studies. GRADE methods will be used to assess certainty of evidence and summarise findings.

Results of the systematic review will provide a comprehensive and up-to-date synthesis of evidence about the effectiveness of aromatherapy.

Systematic review registration

PROSPERO CRD42021268244

In 2015, the Australian Government conducted a Review of the Australian Government Rebate on Natural Therapies for Private Health Insurance (2015 Review). Underpinned by systematic reviews of evidence for each natural therapy, one of the findings from the 2015 Review was that there was no clear scientific evidence that aromatherapy was effective. This protocol for a systematic review of aromatherapy describes the methodology for one of a suite of independent evidence evaluations commissioned by the Australian Government Department of Health (the Department) via the National Health and Medical Research Council (NHMRC) to update the evidence and inform the Review of the Australian Government Rebate on Private Health Insurance for Natural Therapies 2019-20 (2019-20 Review) [ 1 ].

Aromatherapy is one of the most widely used natural therapies reported by consumers in Western countries. A systematic review of 89 surveys (97,222 participants), estimating the prevalence of complementary medicine (CM) use by consumers in the UK, found that aromatherapy was the third most popular CM from among 28 different therapies [ 2 ]. In Australia, a cross-sectional survey examining consultation with complementary therapists and use of complementary medicine products found that about half of all respondents (1016/2025 adults) used complementary medicines [ 3 , 4 ]. Aromatherapy oils were used by 11% of respondents ( N = 224/2019), and 3.9% of respondents had visited an aromatherapist ( N = 79/2019) [ 4 ]. Based on the average spending on complementary medicines reported in this survey, the study authors estimated the total expenditure on aromatherapy oils in Australia to be AUD 250 million in the previous 12 months (2016–2017) [ 3 ].

Description of the intervention

Aromatherapy is the therapeutic use of essential oils from plants (flowers, herbs or trees) to treat ill health and promote physical, emotional and spiritual well-being [ 1 , 5 , 6 ]. The name ‘aromatherapy’ suggests that treatments are delivered directly or indirectly through the olfactory system and that ‘aroma’ is central to therapeutic action. However, there are multiple modes of administration, and these include treatments intended to act through direct contact with the skin and inhalation into the lungs (rather than through an ‘aroma’ inhaled through the olfactory system). The inclusion of such therapies within the scope of aromatherapy practice has led some professional groups to suggest that a more apt description is ‘essential oil therapy’ [ 7 ].

Active ingredients and choice of essential oils

Although the scope of aromatherapy practice varies, the use of essential oils is central to all definitions [ 6 , 7 , 8 , 9 , 10 ]. Essential oils are volatile oils extracted using steam distillation or mechanical expression from aromatic plants [ 6 , 11 ]. While it is possible to extract essential oils using solvents (‘absolutes’) and to produce synthetic versions of some oils, aromatherapists generally consider that these are not true essential oils and are therefore unsuitable for therapeutic use [ 6 , 11 ].

Essential oils vary greatly in their molecular composition. This composition determines the aroma of each oil, and the pathways by which it is absorbed, distributed and metabolised to produce effects [ 6 , 11 ]. Aromatherapists tailor treatments to individual needs, selecting essential oils, and their mode of application, based on anticipated therapeutic properties for the targeted condition [ 1 , 6 ].

Mode of administration and dose

Inhalation through passive diffusion in the air (e.g. through mist or heat diffusers, steam vaporisation) and direct inhalation (e.g. individual inhalers, steam inhalation) can be used as the primary mode of administering essential oils. Topical application of diluted essential oils to the skin is also common [ 6 ]. The intention of topical application may be to produce local effects at the point of administration (e.g. to alleviate pain in a joint) and to mediate effects through inhalation (whether through the lungs or olfactory system) or through skin absorption. Massage is a common co-intervention used with topical application of essential oils. While massage may have a therapeutic effect when used independently of essential oils, it is generally described as an ‘integral’ part of aromatherapy treatment [ 7 ]. For topical application, essential oils are diluted in a carrier oil, usually vegetable or nut oil (e.g. sweet almond oil, grapeseed, jojoba oil) [ 12 ]. These carrier oils differ from essential oils in that they contain fatty acids, vitamins and minerals, and are believed to aid absorption of the essential oil through the skin [ 12 ].

Limiting the dose or concentration of essential oils is considered an important means of avoiding systemic toxicity or adverse effects, such as skin irritation or sensitivity [ 11 , 12 ]. The typical dose of essential oil used for therapeutic purposes varies depending on indication, and the oil and route of administration, but is generally in the range of a 2.5–5% dilution of essential oils for topical use [ 11 ]. Lower concentrations (i.e. higher dilutions) are recommended for some population groups, including women who are pregnant, children and people with conditions or receiving treatments/medications that may put them at greater risk of adverse effects (e.g. people with skin conditions or damage; people undergoing radiotherapy; people with asthma) [ 7 , 11 ].

Although other routes of administration are sometimes used, professional associations for aromatherapists in Australia, the UK, Canada and the USA have position statements recommending against ingestion of essential oils, internal use (on or near mucous membranes) and the use of undiluted essentials oils on the skin [ 7 , 8 , 9 ].

Practitioners of aromatherapy and regulation

Aromatherapy is practised by natural therapists, including aromatherapists, naturopaths and massage therapists. It is also an increasingly common professional education option for nurses, allied health professionals and those working in sectors such as palliative care.

Aromatherapy practice is not regulated by the Australian Health Practitioner Regulation National Law, which means there is no requirement for professional registration of practitioners of aromatherapy [ 13 , 14 ]. The International Aromatherapy and Aromatic Medicine Association (IAAMA) offers membership to aromatherapy practitioners in Australia who have completed accredited training through the National Quality Training Framework [ 15 ]. The IAAMA, and other associations for natural therapists in Australia, also set standards for practice and ethical conduct and have requirements for continuing professional education [ 15 , 16 ]. Some professional associations have safety guidelines and position statements aimed at preventing the use of contraindicated oils, unsafe therapies and treatments that are not widely accepted by the profession (for examples, see [ 7 , 8 , 9 , 10 ]).

In the 2016–2017 cross-sectional survey examining use of complementary medicine products, only a minority of those who reported therapeutic use of aromatherapy oil consulted a complementary medicine practitioner (12.5%) for a prescription, whereas self-prescription was common (43%) [ 3 ]. Indeed, part of the appeal of aromatherapy may be the accessibility of essential oils, which do not require a prescription. The Australian Government provides a safeguard for consumers by regulating essential oils intended for therapeutic use through the Therapeutic Goods Administration (TGA). However, most essential oils are designated as lower risk medicines, which means they are assessed by the TGA for quality and safety, but not effectiveness [ 17 ].

How aromatherapy might work

The research literature and guidance on aromatherapy describes multiple theories of how aromatherapy works (for examples, see [ 6 , 7 ]). This is perhaps unsurprising given that the exact mechanism by which aromatherapy brings about effects is likely to differ according to the molecular composition of the essential oil and the mode of administration. Similarly, the mechanism of action may vary across outcomes. For example, the mechanism(s) through which aromatherapy might relieve pain may be different from the mechanism for relieving nausea and vomiting [ 18 ]. If massage is used as a co-intervention, then the interaction between massage, the essential oil and the carrier oil may also influence the mechanism [ 6 , 12 ]. Research on these mechanisms comes predominantly from mainstream neurophysiological research on olfaction and pharmacological research. Some is specific to essential oils, but very little originates from literature on aromatherapy [ 6 ]. This research is comparatively recent, and evidence about the mechanisms of action for specific oils and modes of delivery is limited [ 6 , 19 ].

The prevailing description of how aromatherapy works — and one that aligns intuitively with the practice of aromatherapy — is that aromatherapy acts through the olfactory system. Volatile molecules in the aromatherapy oil (the odorant) interact with receptors in the nose, generating an electrical signal to the brain that triggers the perception of smell [ 6 , 19 , 20 ]. This perception includes responses initiated in the limbic system, which is involved in controlling memory and emotion, and through which odours are thought to produce effects on mood, alertness, mental stress, arousal and perceived health [ 6 ]. Biochemical or physiological pathways are likely to mediate the effects of essential oils applied to the skin, where either local or systemic effects may be possible depending on whether the active component diffuses through the skin [ 19 ]. Some of these effects are suggested to arise from antibacterial, anti-inflammatory and analgesic properties of essential oils [ 6 , 21 , 22 ].

Aromatherapy professional associations also describe a pathway involving an ‘energetic’ or spiritual response. Such mechanisms are described as a ‘vibrational interaction’ between the active component of the essential oil and ‘the energy flows within the body’ [ 7 ]. It is unclear whether this pathway relates to the disproven theory that posits a vibrational mechanism of olfaction in which the olfactory system detects molecular vibrations of odour molecules [ 7 , 20 , 23 ].

Description of conditions for which aromatherapy is used

Although texts on aromatherapy describe a breadth of clinical indications, aromatherapy is often used to treat symptoms of a condition and the side effects of treatment rather than the underlying condition. Examples include the use of aromatherapy to alleviate pain, symptoms of anxiety (that occur as a reaction to stress), low mood, sleep disturbance, behavioural disturbance, vomiting and nausea, and fatigue [ 6 , 24 , 25 , 26 , 27 ]. These indications align with the most commonly treated conditions reported in a 2015 survey completed by 36 practising aromatherapists in Australia [ 14 , 28 ]. Stress was the condition most frequently reported as ‘often treated’ (by 79% of aromatherapists). Musculoskeletal conditions associated with chronic pain were also frequently reported as often treated, especially neck (64% of aromatherapists), arthritis (54%), sciatica (42%) and knee pain (42%). Other conditions that were reported as ‘often treated’ were headache and migraine (66%), mental health conditions (40%), insomnia (47%), sports injury (27%), cancer (24%) and palliative care (21%).

There is a particular interest in using aromatherapy in circumstances where mainstream interventions may not provide satisfactory relief of symptoms, for example for people with unremitting chronic pain, cancer or advanced disease (not amenable to cure) [ 6 , 25 , 29 , 30 ]. Among people with cancer and advanced disease, aromatherapy is used as a form of supportive care to enhance physical and emotional well-being, in addition to alleviating specific symptoms [ 6 , 25 , 29 , 30 ]. In other cases, aromatherapy is used as an alternative or adjunctive therapy by those seeking to avoid pharmacological or invasive treatment. For example, aromatherapy has been used to ameliorate behavioural and sleep disturbances among people with dementia [ 24 ], to relieve pain during labour [ 31 ] and to treat postoperative nausea and vomiting [ 32 ]. These treatments may be delivered in a range of healthcare settings (primary, acute and subacute care), with varying levels of integration with conventional providers [ 33 ].

Because aromatherapy is often sought or prescribed for relief of symptoms, those receiving aromatherapy for the same indication may have very different underlying conditions (e.g. cancer, arthritis, chronic insomnia) or be undergoing different treatments (e.g. surgery, chemotherapy, minor procedures). Examining the effects of aromatherapy on outcomes for a particular condition may be of interest in some circumstances, but for many commonly treated symptoms or side effects, there is no clear clinical rationale for why the effects of aromatherapy would differ importantly by condition. Where this is the case, a broad synthesis across conditions addresses whether there is a consistent effect for the outcome of interest (benefit, little or no effect, harm), in addition to enabling exploration of whether the effect of aromatherapy differs by condition (e.g. smaller or larger effects).

Why it is important to do this review

This systematic review will inform the Australian Government’s Natural Therapies Review 2019-20, which is evaluating evidence of the clinical effectiveness of 16 therapies (including aromatherapy). The conclusion from the evidence evaluation conducted on aromatherapy for the 2015 Review was that ‘there was no clear evidence demonstrating efficacy of aromatherapy’ [ 34 ]. The evidence evaluation used overview methods, synthesising results from 20 systematic reviews published up to May 2013. Of the primary studies included in these systematic reviews ( N = 45), all but one were published prior to 2012. Since the completion of the original evidence evaluation, there has been substantial growth in published research on aromatherapy. A bibliometric analysis of scientific articles on aromatherapy found a steady increase in the number of primary studies and reviews from 1995 to 2014 [ 35 ]. Of the 549 research articles published in this period, a third ( N = 190) were published between 2012 and 2014. This finding marries with claims that there may be evidence available (either published in the last 5 years or not incorporated in systematic reviews at the time the overview was conducted) that may change the conclusions about the effects of aromatherapy [ 1 ]. In contrast to the 2015 aromatherapy evidence evaluation, this review will examine evidence from eligible primary studies published from database inception until the date of the last search for this systematic review.

The overall objective of this systematic review is to examine the evidence for the clinical effectiveness of aromatherapy in preventing and/or treating injury, disease, medical conditions or preclinical conditions [ 1 ]. The review will focus on outcomes (and underlying conditions) for which aromatherapy is commonly sought or prescribed in Australia, and which are relevant to the 2019-20 Review of the Private Health Insurance rebate. The specific objectives of the review follow (framed as questions). Examples of potentially relevant outcome domains and conditions are included to illustrate the breadth of questions to be addressed in the synthesis. These questions will be refined through a staged prioritisation process (‘ Methods ’ section, Fig. 1 ) to align with priorities for the 2019-20 Review, ensure a consistent approach across the evidence evaluations of natural therapies (where appropriate) and make best use of available evidence.

figure 1

Staged approach for developing the analytic framework for this review

Primary objectives

What is the effect of aromatherapy compared to no aromatherapy (inactive controls) (see the section ‘ Types of interventions ’ — Comparisons) among people with any condition, pre-condition, injury or risk factor on outcomes for which aromatherapy is indicated? (for example, acute pain, emotional functioning and well-being, sleep disruption, behavioural disturbances, health-related quality of life)

What is the effect of aromatherapy plus massage compared to massage alone among people with any condition, pre-condition, injury or risk factor on outcomes for which aromatherapy is indicated? (examples as per objective 1)

Secondary objectives

What are the effects of aromatherapy for each underlying condition, pre-condition, injury or risk factor? (for example, effects on sleep disruption among people undergoing palliative care, people with chronic insomnia, people with chronic pain or people with dementia)

What are the effects of aromatherapy compared to evidence-based ‘gold standard’ treatments ? (see the section ‘ Types of interventions ’ — Comparisons)

What evidence exists examining the effects of aromatherapy compared to other active comparators? (i.e. not massage or a ‘gold standard’)

Methods reported in this protocol are based on the Cochrane Handbook for Systematic Reviews of Interventions [ 36 ]. The GRADE approach will be used to summarise and assess the certainty of evidence arising from this review (see the ‘ Data collection and analysis ’ section for details). GRADE methods are widely used in systematic reviews and guideline development to ensure a systematic, transparent and common approach to interpreting results [ 37 ]. The protocol is reported in accordance with the Preferred Reporting Items for Systematic review and Meta-Analyses Protocols (PRISMA-P) statement [ 38 , 39 ] with consideration given to the extensively updated guidance for reporting methods for systematic review in the Preferred Reporting Items for Systematic review and Meta-Analyses (PRISMA) 2020 statement [ 40 , 41 ]. The review has been prospectively registered on the International prospective register of systematic reviews (PROSPERO CRD42021268244 ).

The methods for this review are designed to accommodate the breadth of evidence about the effects of aromatherapy relevant to the 2019-20 Review and ensure a consistent approach with the other evidence evaluations of natural therapies (where appropriate). To achieve this, we will follow the staged approach summarised in Fig. 1 and elaborated in subsequent sections. We begin with an initial analytic framework (step 1) that will be refined through a prioritisation process. To facilitate this process, we will screen studies against the review eligibility criteria and compile an aggregate list of populations and outcomes, derived from the included studies and organised by the initial framework (step 2). No identifying information will be included (i.e. no study-level information, results, references, number of studies etc.). The NHMRC’s Natural Therapies Working Committee (NTWC) and the Department’s Natural Therapies Review Expert Advisory Panel (NTREAP) will review the list in order to prioritise outcomes and advise on the final framework for the synthesis (step 3), which will be finalised (step 4) prior to proceeding with the review (step 5).

Figure 2 shows the initial analytic framework for the review. Example populations and outcome domains are included to convey the breadth of the review, and illustrate possible population and outcome groups for synthesis. These are indicative and not intended to be exhaustive. The framework was informed by research on the outcomes (and underlying conditions) for which aromatherapy is commonly sought or prescribed in Australia, a scoping search of studies evaluating aromatherapy, the wider literature on aromatherapy and consideration of frameworks for classifying disease and outcomes [ 42 , 43 ]. Details for each population, intervention, comparator, outcomes (PICO) element follow (see the ‘ Criteria for considering studies for this review ’ section).

figure 2

Initial analytic framework for the review. 1 Excluding oils considered unsafe for therapeutic use in humans. 2 Excluding ingestion, internal administration or undiluted application to the skin. 3 Synthesis limited to inactive, massage (when aromatherapy is delivered via massage) and evidence-based ‘gold standard’ treatments. 4 Symptoms relevant to each population group will vary

Criteria for considering studies for this review

Types of studies.

Randomised controlled trials (RCTs) are eligible for inclusion in the review (including individually and cluster randomised and cross-over trials).

Controlled trials in which the allocation sequence did not include a truly random element, was predictable or was not adequately concealed from investigators are eligible as long as there was an attempt to have some kind of ‘randomisation’ to groups. Examples include studies using methods for sequence generation based on alternation, dates (of birth or admission) and patient record numbers [ 44 ].

Non-randomised studies of interventions (NRSIs)

Studies described as ‘randomised trials’ or ‘controlled clinical trials’, but in which decisions about the allocation of participants to treatment groups were (1) made by clinicians or participants or (2) based on the availability of the intervention. These studies lack any ‘attempt’ at randomisation and, as such, are likely to be at high risk of selection bias whereby participants may be selected into groups based on factors that are prognostic of outcomes (which may introduce confounding). These studies will be treated as non-randomised studies.

Studies for which available reports have not been peer reviewed (grey literature)

The decision to exclude non-randomised studies was informed by scanning results from a scoping search of the Cochrane Central Register of Controlled Trials (CENTRAL) (see the ‘ Electronic searches ’ section) and results of a more limited search of PubMed using a resource on the National Institute of Health National Centre for Complementary and Integrative Health website [ 45 ]. The scoping search of CENTRAL retrieved in excess of 500 potentially eligible trials, from which we anticipate a high proportion (100–200) will meet eligibility criteria for the review. Given the likely size and breadth of the evidence base, and the proposed structure for the synthesis, any effect of aromatherapy on health outcomes should be detectable from randomised trials. The inclusion of NRSIs is unlikely to increase certainty of the results from a body of randomised trial evidence of this size or alter the conclusions of the review.

Date and language restrictions

There are no restrictions on publication date.

Potentially eligible studies published in languages other than English will not be included in the review, but will be listed according to whether they are likely to be eligible or whether eligibility cannot be determined (see the ‘ Selection of studies ’ section). The impact of excluding these studies will be considered in the assessment of bias due to missing results (see the ‘ Assessment of biases due to missing results ’ and ‘ Summary of findings tables and assessment of the certainty of the body of evidence ’ sections).

Types of participants

Studies involving participants with any disease, medical condition, injury or preclinical condition are eligible for the review. This includes healthy participants with clearly identified risk factors (e.g. biomedical, health behaviours or other). There are no restrictions on age.

We expect that studies will include participants that fall within broad population groups, such as those shown in Fig. 2 . These are indicative groups, included to illustrate the breadth of populations eligible for the review and possible groupings for synthesis. Decisions about which groups to include in the final analytic framework will be made through the prioritisation process (Fig. 1 ). This process may lead to changes and additions to the population groups (i.e. broader, narrower or new groups).

Basis for grouping

Because of the broad range of indications for aromatherapy (e.g. management of symptoms of a condition or side effects of treatment for a condition, versus treatment of an underlying condition), the basis of the population groups shown in the initial analytic framework varies. Some are grouped by symptom (e.g. chronic pain), some by treatment for an underlying condition (e.g. surgery and other procedures) and others by the underlying condition (e.g. chronic insomnia, dementia). The groupings are based on International Classification of Diseases 11th Revision (ICD-11) codes and encompass conditions identified in aromatherapy literature and the Practitioner Research and Collaboration Initiative (PRACI) survey as often treated by aromatherapists [ 14 , 28 ].

Participants who are otherwise healthy will be considered to have a clearly identified risk factor if participating in a trial aimed at prevention of a disease/condition for which their risk factor is an eligibility criterion (e.g. individuals with signs or symptoms of work-related anxiety who are confirmed to be at risk of developing a clinically diagnosed anxiety or fear related disorder).

Healthy populations seeking health improvement

Studies that include both healthy participants and participants eligible for the review will be included if separate data are available or a majority of participants meet the review eligibility criteria as per guidance in the Cochrane handbook [ 46 ]. For the latter, we will consider implications for the applicability of study findings in the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) assessment.

While studies involving any population will be included in the review (except for the specific exclusions above), if the number of eligible studies for synthesis is unmanageable, the synthesis may be limited to populations (conditions) most relevant to aromatherapy practice in Australia. Such decisions will be made through the prioritisation process (Fig. 1 ), guided by data about practice in the Australian context (e.g. practitioner or patient surveys that report reasons for use in Australia). Studies excluded from the synthesis will be included in an evidence inventory (objective 5).

Types of interventions

For the purpose of this review, aromatherapy is defined as ‘Administration of aromatherapy oils by inhalation, diluted topical use and massage’ [ 1 ].

Except for the specific exclusions below, aromatherapy treatments will be eligible irrespective of the type of essential oil, carrier or dispersant, mode of delivery or route of administration, whether self-administered or provided by a practitioner, the training or qualifications of the practitioner and the dose and duration of treatment. More details about each of these intervention features are considered under the ‘ Data extraction and management ’ section. See also Appendix 3, Additional file 1 .

Excluded therapies

In line with the recommendations from aromatherapy professional associations in Australia and internationally [ 7 , 8 , 9 , 10 ], we will exclude interventions in which an essential oil is:

Ingested or administered internally (e.g. oral, vaginal, rectal or other internal routes of administration)

Applied undiluted to the skin

Considered unsafe for therapeutic use in humans

Comparisons

Aromatherapy (delivered by any mode, including massage) versus any inactive comparator (placebo/sham, no intervention, wait list control, usual care)

Aromatherapy delivered by massage versus massage alone (this comparison is included to isolate the effects of aromatherapy)

Aromatherapy (delivered by any mode) versus evidence-based gold standard treatment(s) (see below for selection method)

Aromatherapy (delivered by any mode) versus other active comparators (for inclusion in evidence inventory only, not the synthesis — see below)

These comparisons will form the basis of separate syntheses (meta-analyses), each considering an outcome domain with studies grouped within by population group (where appropriate; see Fig. 2 for examples). Where a study includes multiple arms, with at least one eligible comparator (e.g. a placebo control arm), we will include the eligible comparison(s).

For comparison 3, evidence-based gold standard treatments will be identified through the prioritisation process (Fig. 1 , step 3). We will provide the NTWC and NTREAP with a list of active comparators identified from included studies (Fig. 1 , step 2). Studies with active comparators will not contribute to the synthesis except in the exceptional circumstance where the NTWC considers that the comparator intervention is an accepted, evidence-based ‘gold standard’ of care for the population in the studies, and there are studies suitable for conducting a synthesis (meta-analysis) (i.e. comparable PICO criteria, low risk of bias). These judgements will be made blinded to the studies and study results, to the fullest extent possible. For studies involving other active comparators, we will provide an inventory of available evidence, tabulating a brief description of the characteristics of PICO for each study.

In line with the main review objective, which is to examine the effects of aromatherapy rather than the comparative effects of different aromatherapy treatments, we will exclude head-to-head comparisons of aromatherapy from the review (see exceptions below). For example, we will exclude studies where the only comparator is:

Another essential oil or preparation of an essential oil (e.g. lavender versus ginger)

A different dilution or dose of the same essential oil

A different carrier of the same essential oil

A different mode of delivery of the same essential oil (e.g. two different modes of inhalation; inhalation versus massage)

Where the person administering the therapy has a different qualification, specialisation or skill level (e.g. aromatherapists versus other health professional; this includes comparisons of self-administration versus administration by a practitioner)

Or combinations of the above

Types of outcomes

Outcomes eligible for this review are those that align with the reasons why aromatherapy is sought by patients and prescribed by practitioners. In principle, this may include any patient-important outcome that helps elucidate the effects of aromatherapy on an underlying condition or its symptoms, recovery, rehabilitation or prevention of disease among people with specific risk factors or pre-conditions.

Example outcome domains are shown in Fig. 2 . Appendix 2 in Additional file 1 provides examples of specific outcomes within each domain, and populations to which the outcome domain may be relevant. Because aromatherapy is often used for the management of symptoms of a condition or side effects of treatments (anxiety, pain, nausea and vomiting), ‘symptoms’ are separated from ‘condition-based’ outcomes (the latter encompassing outcomes of relevance when aromatherapy is used to treat the underlying condition). The example outcome domains are intended to illustrate the breadth of outcomes likely to be important for understanding the effects of aromatherapy across a wide range of conditions, as identified from the PRACI survey of the conditions often treated by aromatherapists in Australia [ 14 , 28 ] and the wider literature on aromatherapy.

The initial grouping of broadly related outcomes within each domain (Fig. 2 ) is based on ICD-11 codes and the Core Outcome Measures in Effectiveness Trials (COMET) outcome taxonomy [ 42 , 43 ]. These systems provide a widely agreed and understood structure for categorising different outcomes and address the fact that there is not always a clear distinction between outcomes and conditions. For example, some outcome domains closely match the primary diagnosis for particular patients (e.g. insomnia, chronic pain, anxiety), but are a symptom or side effect of treatment for other conditions (e.g. cancer or surgery).

Prioritisation and selection of outcomes for summary and synthesis

Outcome prioritisation.

To accommodate the breadth of relevant outcomes, the outcome domains and population-specific outcomes for inclusion in the synthesis will be determined through the prioritisation process (Fig. 1 ).

To prioritise the most important outcomes for this review:

We will compile a list of specific outcomes from included studies and example outcome measures (without results or identification of studies).

Outcomes in the list will be categorised by the outcome domains and population groups in Fig. 2 . Outcomes that fall outside the proposed outcome domains will also be listed.

The NTWC will be asked to indicate whether each of the listed outcome domains (or specific outcomes) is critical, important or of limited importance for understanding the effects of aromatherapy on each population group. Only critical and important outcomes will be considered in the review.

Outcome selection

From each study, we will select only one outcome per outcome domain for data extraction (results), risk of bias assessment and inclusion in the summary and synthesis.

An initial hierarchy of population-specific outcomes and measures will be presented to the NTWC for discussion and approval (e.g. a hierarchy of pain outcomes and measures for osteoarthritis).

Where possible, the initial hierarchy will be based on outcome hierarchies used in published Cochrane reviews, systematic reviews of measures that provide evidence of the relevance and validity of measures, and core outcome sets.

We will also seek advice on the most relevant time point for outcome measurement. This is likely to be immediately post-intervention (end of the intervention period if multiple treatments). In some instances, the longest follow-up may be relevant (e.g. chronic pain).

The agreed hierarchy of population-specific outcomes measures and time points will be used to select the most relevant and valid measure of each outcome domain available from each study for inclusion in the synthesis.

Exclusions:

Experience of care (e.g. satisfaction)

Economic outcomes

Studies will not be excluded from the synthesis/reporting of results based on outcome, except where it is possible to confirm that the study did not measure an outcome eligible for the review (e.g. from a registry record or protocol).

Search methods for identification of studies

Electronic searches.

The primary source of studies will be the Cochrane Central Register of Controlled Trials (CENTRAL), the most comprehensive source of published and unpublished reports of randomised trials. Most CENTRAL records are derived from regular searches of bibliographic databases, such as MEDLINE, Embase and the Cumulative Index of Nursing and Allied Health Literature (CINAHL). Records from clinical trial registers (ClinicalTrials.gov and WHO International Clinical Trials Registry Platform [ICTRP]) and the specialised registers maintained by Cochrane groups also make up a substantial proportion of records in CENTRAL.

As part of Cochrane’s centralised search service, the major bibliographic databases and trial registers are searched monthly and, using a combination of automation and crowd screening, records deemed to be reports of randomised trials are added to CENTRAL [ 47 ]. In a recent evaluation, over 97% of studies included in Cochrane reviews were retrieved by Cochrane’s centralised search service [ 48 ]. Given the large volume of studies we anticipate will be eligible, we are confident that limiting our search to CENTRAL, with supplementary searches of PubMed and the Allied and Complementary Medicine Database (AMED), will capture a very high proportion of all relevant studies.

The proposed search strategy for CENTRAL includes the key thesaurus terms and text words for aromatherapy, as well as more peripheral terms, such as essential oils (see Appendix 1 in Additional file 1 ). The most commonly used essential oils are included as text words in their own right. This list of oils was compiled from (1) studies included in the overview of aromatherapy for the 2015 Review [ 34 ] and (2) the broader aromatherapy literature [ 6 , 21 , 22 , 24 , 25 , 26 , 27 , 31 ]. To ensure no commonly used essential oils were missing from the list, we examined a sample of 272 abstracts from a PubMed Clinical Query for aromatherapy (category: ‘Therapy’, scope: ‘Narrow’). We will not limit the search by language, year of publication or publication status.

Since there is a lag between when records are processed by Cochrane and when they appear in CENTRAL, we will run a search in PubMed for records added in the previous 6 months. In addition, to ensure we include records available in PubMed but which are not indexed in MEDLINE, we will search PubMed for all years, limited to the non-MEDLINE subset (see Appendix 1 in Additional file 1 ).

We will also search AMED and Emcare via Ovid as these databases are not ones that Cochrane searches centrally.

Scoping searches reveal that about 500 records in CENTRAL (excluding records from ClinicalTrials.gov or WHO ICTRP) are either indexed with the Medical Subject Headings (MeSH) or Emtree term Aromatherapy or have aromatherapy as a text word in the title. A further 1300 records are retrieved with the remaining search terms.

Searching other resources

We will screen studies provided by the public and key stakeholders (via the Department), NTREAP and NTWC for eligibility. Where these groups recommend particular systematic reviews, we will examine references for included studies to identify potentially eligible randomised trials.

We will ensure that all randomised trials included in the 2015 evidence evaluation for aromatherapy are considered for inclusion.

We will not examine the reference lists of included studies to identify additional trials (i.e. backward citation searching), nor will we conduct forwards citation searching (i.e. looking for studies that have cited included studies). Empirical studies assessing the value of reference checking (backward citation searching) as part of the systematic review process indicate that it is most useful for areas that are difficult to search electronically (new technologies, cross-disciplinary topics, complex interventions) or for which review authors aim to locate grey literature [ 49 ]. Forward citation searching is much less common in systematic reviews [ 50 ] and of questionable value [ 51 ]. Conducting forward citation searching for the large volume of aromatherapy studies we anticipate including in this review could generate thousands of additional records to screen, with little evidence that we would identify unique studies. This has significant time and cost implications [ 52 ]. We anticipate that our search is sufficiently sensitive that we are unlikely to miss important studies, and given the anticipated volume of eligible studies and breadth of the review question, it is unlikely that any missing studies would alter the findings of the review.

Data collection and analysis

Selection of studies.

Records from CENTRAL, PubMed and AMED will be imported into EndNote and duplicates removed. All remaining records will be imported into Covidence [ 53 ] for screening. Records submitted through the Department, NTREAP or NTWC will be screened to confirm that the type of study is eligible, then non-duplicate records will be imported into Covidence for screening alongside other studies.

We will pilot guidance for title and abstract screening on a sample of 50 records to ensure the eligibility criteria are being applied consistently by three reviewers (SB, MM, SM). If needed, we will amend the screening guidance (but not the eligibility criteria) to enhance consistency. We propose to split title and abstract screening into two phases. Phase 1 records (indexed with the thesaurus terms Aromatherapy or Oils volatile or with aromatherapy in the title) will be screened independently by at least two reviewers. Phase 2 (remaining records) will be screened by one reviewer, with a 10% random sample screened by a second reviewer (with further sampling if needed until 80% agreement is achieved). All records selected for full-text screening will be reviewed independently by two reviewers. Disagreements at either stage of screening will be resolved by consensus among members of the review team. Where disagreement cannot be resolved, advice will be sought from the NTWC (which will be provided with PICO characteristics for the de-identified study).

Studies confirmed as meeting the eligibility criteria, but for which results are not available in a published report, will be included in a list of ‘ongoing studies’.

The following will be included in a list of ‘studies awaiting classification’.

Studies that are only published as abstracts or for which a full report is not available (i.e. we will not seek further information from study authors to confirm eligibility)

Studies identified by, or submitted to, the review team after the date of the last search

Studies confirmed as likely to be eligible, but for which no English language translation of the full-text publication is available. Studies for which eligibility cannot be confirmed following translation of the title and abstract using Google Translate will be listed separately (Fig. 3 ).

figure 3

Flowchart showing handling of studies in languages other than English (reproduced from NHMRC framework for natural therapies systematic reviews [ 54 ])

Studies that do not meet the eligibility criteria will be excluded and the reason for exclusion will be recorded at full-text screening. These studies will be included in a ‘Characteristics of excluded studies’ table in which the reason for exclusion is reported.

The search and study selection steps will be summarised in a PRISMA flow diagram.

For studies that originated from the call for evidence, NTREAP or NTWC, we will record and report exclusion decisions irrespective of whether the study was excluded during title and abstract screening or full-text review. We will document the flow of these studies through the review in the PRISMA flow chart and annotate tables with the source.

Dealing with duplicate and companion publications

Multiple publications to the same study (e.g. protocols, trial registry entries, trial reports) will be identified and linked at the data extraction stage in Covidence systematic review management software [ 53 ]. Each study will be given a unique identifier and all linked records cited in the final report. Records will be matched using trial registry numbers. Where these are not available, we will consider author names, trial name, trial location(s) and number of participants.

Data extraction and management

Study data will be collected and managed using REDCap electronic data capture tools hosted at Monash University [ 55 , 56 ]. Three authors (MM, SB or SM) will pre-test the data extraction and coding form on 3–5 studies (as needed to achieve consistent coding), purposefully selected from the included studies to cover the diversity of data types anticipated in the review. One author (SB) will review the extracted and coded data for completeness, accuracy and consistency. Where needed, advice will be sought from the clinical advisor (SG) and biostatistician (JM) to ensure data are extracted as planned. Revisions to the data extraction form and guidance will be made as required to maximise the quality and consistency of data collection.

For each included study, one review author (MM, SB or SM) will extract study characteristics and quantitative data using a pre-tested data extraction and coding form, with a 10% random sample extracted by a second author (with further sampling if needed until 80% agreement is achieved). For studies extracted by a single author, a second author (MM, SB or SM) will independently verify the quantitative data. Discrepancies will be resolved through discussion, and advice sought from the clinical advisor (SG) or biostatistician (JM) if agreement cannot be reached or for more complex scenarios.

We will extract information relating to the characteristics of included studies and results as follows.

Study identifiers and characteristics of the study design

Study references (multiple publications arising from the same study will be matched to an index reference; code as index paper, protocol, registry entry, results paper 1, 2, …)

Study name, location, commencement date and trial registration number

Study design (categorised as ‘individually randomised’, ‘cluster randomised’, ‘cross-over’ or ‘other’)

Funding sources and funder involvement in study

Financial and non-financial interests declared by investigators

Characteristics of each intervention group (including comparator groups)

Characteristics of the intervention structured by domains of the Template for Intervention Description and Replication (TIDieR) checklist [ 57 ] (see Appendix 3 in Additional file 1 for TIDieR domains, codes and an example of coding for aromatherapy)

Number of participants: randomised to each group, at follow-up for selected outcome, and included in analysis and reasons for loss to follow-up

Characteristics of participants

Participant eligibility criteria (verbatim)

Age (e.g. mean, median, range)

Population group: coded using categories specified in the final analytic framework for the review (e.g. chronic pain, headache and migraine, cancer and advanced disease (not amenable to cure), surgery or procedures, pregnancy and childbirth, chronic or insomnia, dementia, stress, anxiety and mood disorders)

Condition: specific underlying condition as described in study (e.g. haematological tumours; rheumatoid arthritis), including information about severity (if relevant)

Treatment/procedure: applies to studies in which aromatherapy is administered for the relief of symptoms or side effects of a treatment or procedure for an underlying condition (e.g. radiotherapy; bone marrow biopsy). May include pharmacological treatment, surgical, diagnostic or other procedures (as described in study, and coded using categories specified for the review e.g. pharmacological, surgery, minor or major non-surgical procedure)

Other characteristics of importance within the context of each study

Outcomes assessed and results

Outcomes measured (a list of all outcomes [noting primary outcome(s) for study], categorised according to the broad domains specified in the final analytic framework for the review, or as ‘other’ if none of the outcome domains applies)

For outcomes selected for inclusion in the summary and synthesis of results:

Outcome domain: categorised according to the broad domains specified in the final analytic framework for the review (e.g. pain, sleep disturbances, nausea and vomiting, emotional functioning/well-being, behavioural disturbances, cognitive functioning, fatigue, health-related quality of life)

° Outcome as described in the included study (verbatim or precis)

° Measurement method (e.g. Rotterdam Symptom Checklist, used to measure psychological and physical aspects of quality of life for people with cancer), information required to interpret the measure (scale range and direction, minimally important difference) and time point (exact, and time-frame categorised as ‘immediate’ or ‘longest follow-up’)

° Results including summary statistics by group (means and standard deviations, or number of events for cognitive outcomes that have been dichotomised, and sample size), estimates of intervention effect (e.g. mean differences (or adjusted mean differences), confidence intervals, t -values, p -values or risk ratios/odds ratios for binary outcomes)

° Data required to support risk of bias judgements (see the ‘ Assessment of risk of bias of included studies ’ section) [ 58 ]

Assessment of risk of bias of included studies

Assessment of risk of bias in rcts.

We will assess the risk of bias in included studies using the revised Cochrane ‘Risk of Bias’ tool (RoB 2) for randomised trials [ 44 , 58 ] for each critical (or important) outcome included in the synthesis. Our assessment will be based on the effect of assignment to the intervention .

RoB 2 addresses five domains:

Bias arising from the randomisation process

Bias due to deviations from intended interventions

Bias due to missing outcome data

Bias in measurement of the outcome

Bias in selection of the reported result

To promote concordance, the assessment will be piloted by three review authors (MM, SB, SMc) on 3–5 studies until consistent judgements are achieved across a range of scenarios. One review author (MM, SB or SMc) will then apply the tool to the selected results from each study following the RoB 2 guidance [ 44 ], and a second author will verify the assessments (SB or SMc). Supporting information and justifications for judgements for each domain (low, some concerns, high risk of bias) will be recorded. We will derive an overall summary of the risk of bias from each assessment, following the algorithm in the RoB 2 guidance [ 45 ]. Disagreement between review authors will be resolved through discussion, and a third review author (SB, SM or JM) will adjudicate where agreement cannot be reached. For cluster trials and cross-over trials, we will use the variant of the RoB 2 tool specific for the design [ 59 ].

When multiple effects of the intervention using different approaches are presented in the trial report, we will select one effect for inclusion in the meta-analysis and for risk of bias assessment. The selected effect will be chosen according to the following hierarchy, which orders the approaches from (likely) least to most biased for estimating the effect of assignment to the intervention : (1) the effect that corresponds to a full intention-to-treat analysis, where missing data have been multiply imputed, or a model-based approach has been used (e.g. likelihood-based analysis, inverse-probability weighting); (2) the effect corresponding to an analysis that adheres to intention-to-treat principles except that the missing outcome data are excluded; (3) the effect that corresponds to a full intention-to-treat analysis, where missing data have been imputed using methods that treat the imputed data as if they were observed (e.g. last observation carried forward, mean imputation, regression imputation, stochastic imputation); or (4) the effect that corresponds to an ‘as-treated’ or ‘per-protocol’ analysis, or an analysis from which eligible trial participants were excluded [ 58 , 59 ].

Measures of treatment effect

We anticipate that many of the outcomes will be continuous (e.g. pain, anxiety) and that varying measurement instruments will be used to measure the same underlying construct across the studies. For this reason, we will quantify the effects of aromatherapy using the standardised mean difference (SMD) (implementing the Hedges’ adjusted g version). In trials where a continuous measure has been dichotomised (e.g. a continuous pain scale is dichotomised into improvement or no improvement) and analysed as binary outcomes, we will re-express reported, or calculated, odds ratios as SMDs [ 60 ]. For dichotomous outcomes, we will quantify the effects of aromatherapy using risk ratios (RR). Given the wide range of conditions and outcomes in this review, it is not possible to specify specific thresholds for interpreting the size of the effect for each outcome. Given this, we plan to use Cohen’s guiding rules for SMDs where 0.2 represents a small effect, 0.5 a moderate effect and 0.8 a large effect [ 61 ]. Where a valid and reliable minimal important difference (MID) is available for a familiar measure of relevance to the population groups in the meta-analysis, we will re-express the SMD in units of the measure and interpret the effect in relation to the MID if feasible to do so [ 61 ]. For dichotomous outcomes, we will seek advice from the NTWC on interpreting the size of the effect (seeking agreement on a threshold for a small but important difference).

Unit of analysis issues

In this review, unit of analysis issues may arise from non-standard designs (cluster trials, cross-over trials) or from trials with more than two eligible intervention groups. In the following, we outline the methods for making adjustments when necessary. Any adjustments will be documented (e.g. assumed intra-cluster correlation and average cluster size). We will also report when necessary adjustments were unable to be made due to missing information.

For cluster randomised trials that have not appropriately accounted for correlation in observations within clusters, we will attempt a re-analysis. We will do this by inflating the variance of the intervention estimates by a design effect (DEFF). The DEFF is calculated from two quantities — an intra-cluster correlation (ICC) and the average cluster size. Estimates of ICC will be imputed from other cluster trials included in the review, where possible, or by using external estimates from empirical research (e.g. Bell [ 62 ]). The average cluster size will be calculated from reported information in the trial.

For cross-over trials where an appropriate paired analysis is not available, we will attempt to approximate a paired analysis by imputing missing statistics (e.g. correlation). Estimates of the missing statistics will be imputed from other cross-over trials included in the review, where possible, or by using external estimates from empirical research (e.g. Balk [ 63 ]).

For trials where more than one comparison from the same trial is eligible for inclusion in the same meta-analysis (e.g. lavender oil, ginger oil, control), we will combine intervention groups, where it makes sense to do so; otherwise, we will appropriately reduce the sample size so that the same participants do not contribute more than once.

Dealing with missing data

We will not contact trial authors to obtain missing information (e.g. study characteristics, description of conduct of the trial) or aggregate level statistics (e.g. missing standard deviations). However, we will attempt to calculate statistics necessary for meta-analysis using algebraic manipulation of reported statistics (e.g. computing the standard error for the treatment effect from a reported p -value). When standard deviations cannot be calculated from available statistics, but interquartile ranges or ranges are reported, we will use the formula in Wan et al. [ 64 ] to estimate approximate standard deviations. When neither of the above methods are possible, we will impute the standard deviation using the average standard deviation across trials included in the same meta-analysis that have used the same measurement tool. When means are missing, but medians are reported, we will use the formula in Wan et al. [ 64 ] to estimate approximate means.

Our approach for dealing with missing outcome data within the primary trials will be through sensitivity analyses, where trials judged to be at a high or unclear risk of bias will be excluded (see the ‘ Data synthesis ’ section). Risk of bias ‘due to missing outcome data’ is considered within the overall bias judgement for a trial.

Assessment of heterogeneity

We will assess statistical heterogeneity of the intervention effects visually by inspecting the overlap of confidence intervals on the forest plots, formally test for heterogeneity using the χ 2 test (using a significance level of α = 0.1), and quantify heterogeneity using the I 2 statistic [ 65 ].

Assessment of biases due to missing results

We will use a framework for assessing risk of bias due to missing results in which an assessment is made for each meta-analysis regarding the risk and potential impact of missing results from studies (termed ‘known-unknowns’) and the risk of missing studies (termed ‘unknown-unknowns’) [ 66 ]. We will use this framework to guide our assessments of whether there is ‘undetected’ or ‘suspected’ reporting bias for each of the comparisons in our GRADE assessment (see the ‘ Summary of findings tables and assessment of the certainty of the body of evidence ’ section).

In assessing ‘known-unknowns’, we will determine what trials meeting the inclusion criteria for the particular meta-analysis have missing results through examination of the publication’s methods section, trial registry entry (if available) and trial protocol (if available). We will make an assessment as to whether the missing result was potentially due the result itself (e.g. ‘not statistically significant’), and whether inclusion of the result could lead to a notable change in the meta-analysis (e.g. if the missing result is from a large trial). We will also assess the impact of missing results from studies reported in languages other than English that were judged as being likely to meet the eligibility criteria for each synthesis (see the ‘ Types of studies ’ and ‘ Selection of studies ’ sections).

In assessing ‘unknown-unknowns’, we will judge whether the trials not identified were likely to have results eligible for inclusion (e.g. for broad outcome domains such as ‘pain’, it is likely that for particular conditions, missing studies would have been eligible for inclusion). We will use funnel plots and contour-enhanced funnel plots to examine whether there is evidence of small-study effects [ 67 ]. If there is funnel plot asymmetry, we will undertake a sensitivity analysis to compare the combined effect estimated from the random-effects model (primary analysis) with that estimated from a fixed (common) effect model. If the random-effects estimate is importantly larger than the fixed-effect estimate, with no explanation for the difference (e.g. differences in clinical populations or intensity of the delivery of intervention between small and large trials, differences in risk of bias between small and large trials), then we will downgrade for ‘suspected’ reporting bias.

Data synthesis

  • Meta-analysis

Separate comparisons will be set up based on outcome domains agreed in the final framework (see Fig. 2 and Appendix 2 in Additional file 1 for indicative groupings). These comparisons will be stratified by the population groups in the final framework, the basis for which may relate to symptoms (e.g. chronic pain), treatment for an underlying condition (e.g. patients undergoing surgery) or the underlying condition (e.g. chronic insomnia, dementia) (see Fig. 2 and the ‘ Types of participants ’ section for indicative groupings). This approach to structuring the meta-analysis will yield an overall estimate of the effect of aromatherapy for the outcome (review objectives 1, 2 and 4), as well as estimates within each population group (review objective 3). Subgroup analysis by population group will allow examination of whether these population groups explain any observed statistical heterogeneity in the intervention effects (see the ‘Subgroup analysis and investigation of heterogeneity’ section).

We will combine the effects using a random-effects meta-analysis model, since we expect there to be clinical and methodological diversity across the trials that may lead to statistical heterogeneity. These analyses will use the restricted maximum likelihood estimator (REML) of between trial heterogeneity variance and the Hartung-Knapp-Sidik-Jonkman confidence interval method.

Forest plots will be used to visually depict the intervention effect estimates and their confidence intervals. Forest plots will be stratified by condition and risk of bias (within population group).

Summary and synthesis when meta-analysis is not possible

Available effect estimates (95% confidence intervals, p -values), details of scales (direction and range), risk of bias assessments and intervention characteristics will be tabulated. Tables will be ordered by outcome domain, population group and risk of bias assessment.

For a particular comparison, if we are unable to analyse most of the effect estimates (due to incomplete reporting of effects and their variances, variability in the effect measures across the studies), we will consider alternative synthesis methods, such as calculating summary statistics of the effect estimates, combining p -values or vote counting based on the direction of effect [ 68 ]. Our choice of method will be determined by the available data (e.g. summary statistics if data permit; other methods if the data are more limited).

Subgroup analysis and investigation of heterogeneity

We will undertake a subgroup analysis to examine whether population group explains any observed statistical heterogeneity in the intervention effects (see Fig. 2 and the ‘ Types of participants ’ section for indicative population groupings and Appendix 2 in Additional file 1 for the subset of outcomes for which different population subgroups may be relevant). In addition, for the comparison aromatherapy versus inactive comparator, we will consider whether mode of delivery (massage or ‘other’) explains any observed statistical heterogeneity in the intervention effects.

Sensitivity analyses

We plan to undertake and report sensitivity analyses examining if the meta-analysis estimates are robust to the:

Meta-analysis model . In addition to fitting a random-effects model, we will fit fixed-effect models. This analysis will be undertaken to investigate the impact of any small-study effects.

Inclusion of trials judged to be at an overall high or unclear risk of bias. We will exclude trials judged to be at an overall high or unclear risk of bias.

Results of the sensitivity analyses will be tabulated, including the meta-analysis estimate (and its confidence interval), along with details of the original and sensitivity analysis assumptions.

Summary of findings tables and assessment of the certainty of the body of evidence

We will prepare GRADE summary of findings tables for each of the main comparisons, reporting results for critical and important outcome domains (up to seven). For each result, one author (SB) will use the GRADE approach to assess our confidence in where the effect lies relative to our threshold for a small effect (the certainty of evidence) (see the ‘ Measures of treatment effect ’ section). In accordance with detailed GRADE guidance [ 37 , 69 , 70 ], an overall GRADE of high, moderate, low or very low certainty will be reported for each result based on whether there are serious, very serious or no concerns in relation to each of the following domains.

Risk of bias. We will assess the overall risk of bias across all studies contributing to each synthesised result, considering the weight studies rated at high risk of bias contribute to the analysis. Serious or very serious concerns are more likely if studies at high risk of bias contribute considerable weight in the analysis and sensitivity analyses indicate that removing these studies changes the size of the effect (see the ‘Sensitivity analyses’ section).

Inconsistency. We will assess whether there is important, unexplained inconsistency in results across studies considering the overlap of confidence intervals (non-overlap indicating potentially important differences in direction or size of effect), statistical measures that quantify and test for heterogeneity (I 2 statistic, χ 2 test) and, where relevant, results of subgroup analyses (see the ‘ Assessment of heterogeneity ’ section). Where a result is based on a single study, inconsistency will not be rated.

Imprecision. We will assess whether the confidence interval for each pooled effect estimate is wide (e.g. including a small effect and little or no difference, which would lead to different interpretations) and, for large effects, whether the sample size meets the optimal information size (based on number of events for binary outcomes; sample size for continuous outcomes). In judging imprecision, we will use our threshold specified for a small effect (see the ‘ Measures of treatment effect ’ section).

Indirectness. We will assess whether there are important differences between the characteristics of studies included in each synthesis and the question we are seeking to address, such that the effects observed may not apply to our question (i.e. the applicability of the evidence). For example, differences between the interventions delivered and aromatherapy practice in Australia that are likely to influence the size of effect.

Publication bias. Our judgement of suspected publication bias will be based on assessment of bias due to missing results (see the ‘ Assessment of biases due to missing results ’ section). In these assessments, we will consider the potential impact on each synthesised result of excluding studies in languages other than English.

Upgrading domains (large effect size, dose response gradient, opposing plausible residual confounding). There is no precedent for rating up the evidence from randomised trials; however, in principle, these domains apply to any body of evidence so are included here for completeness.

Using GRADE decision rules, we will derive an overall GRADE for the certainty of evidence for each result included in the summary of findings table [ 70 ]. A result from a body of evidence comprised of randomised trials begins as ‘high’ certainty evidence (score = 4) and can be rated down (−1 or −2) for serious or very concerns on any GRADE domain that reduces confidence that aromatherapy has at least a small effect (as determined by the pre-specified thresholds) [ 61 , 69 , 70 ].

Summary of findings tables will be prepared using the GRADEpro GDT software [ 71 ]. The tables will include:

Estimates of the effects of aromatherapy reported as standardised mean differences, and for binary outcomes relative and absolute effects

The overall GRADE (rating of certainty) and an explanation of the reason(s) for rating down (or up) [ 68 ]

The study design(s), number of studies and number of participants contributing data

A plain language statement interpreting the evidence for each comparison and outcome, following GRADE guidance for writing informative statements [ 72 ].

We will present the four levels of certainty of evidence in summary of findings tables with the following symbols and interpretations.

High ( ⊕ ⊕ ⊕ ⊕ ): further research is very unlikely to change the confidence in the estimate of effect

Moderate ( ⊕ ⊕ ⊕ ⊝ ): further research is likely to have an important impact in the confidence in the estimate of effect

Low ( ⊕ ⊕ ⊝ ⊝ ): further research is very likely to have an important impact on our confidence in the estimate of effect and is likely to change the estimate

Very low ( ⊕ ⊝ ⊝ ⊝ ): any estimate of effect is very uncertain

Availability of data and materials

This is a protocol for a systematic review and does not contain any data. Requests for other material should be sent to the corresponding author.

Abbreviations

Allied and Complementary Medicine Database

Cochrane Central Register of Controlled Trials

Cumulative Index of Nursing and Allied Health Literature

  • Complementary medicine

Core Outcome Measures in Effectiveness Trials

Design effect

Grading of Recommendations, Assessment, Development and Evaluation

International Aromatherapy and Aromatic Medicine Association

Intra-cluster correlation

International Classification of Diseases 11th Revision

International Clinical Trials Registry Platform

Medical Subject Headings

Minimal important difference

National Health and Medical Research Council

Non-randomised study of interventions

Natural Therapies Review Expert Advisory Panel

Natural Therapies Working Committee

Population, intervention, comparator, outcome

Practitioner Research and Collaboration Initiative

Preferred Reporting Items for Systematic review and Meta-Analyses

Preferred Reporting Items for Systematic review and Meta-Analyses Protocols

Randomised controlled trial

Restricted maximum likelihood estimator

Risk ratios

Standardised mean difference

Template for Intervention Description and Replication

Therapeutic Goods Administration

National Health and Medical Research Council. Statement of requirement: evidence evaluations for review of natural therapies (tranche two). 2020.

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Acknowledgements

We are grateful to the staff of the ONHMRC for their advice and feedback on the draft protocol and for contributions to text describing the context for 2019-20 Review of Natural Therapies. We thank the NTWC and the NTREAP for their feedback on the draft protocol. We thank John Liman, Senior Software Engineer at Helix, Monash University, for his assistance in developing our data extraction tools in REDCap and Sally Green for contributions to the funding application.

This review was commissioned and funded by the Australian Government Department of Health via the NHMRC under Official Order 2020-21P030 to update the evidence underpinning the 2015 Review of the Australian Government Rebate on Natural Therapies for Private Health Insurance (2015 Review) by the Department of Health (Department). The design and conduct of the review will be done in consultation with the Office of NHMRC (ONHMRC), the NHMRC’s Natural Therapies Working Committee (the Committee) and Department’s Natural Therapies Review Expert Advisory Panel (NTREAP). The NHMRC contracted independent methodological experts to undertake peer review of the protocol and the review report. SB, SM and MM are staff of Cochrane Australia which is funded by the Australian Government through the NHMRC. JEM is supported by an NHMRC Career Development Fellowship (1143429).

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Design of the SR and writing of the original draft protocol was led by SB (overall), SM (search methods and study selection) and JM (analysis plan and question specification). Development of the data extraction tools in REDCap was performed by MM. All authors provided critical review and editing of drafts of the protocol. All authors read and approved the final manuscript.

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Additional file 1: appendix 1..

Database search strategies. Appendix 2. Example outcome domain. Appendix 3. TIDieR domains and example of application in aromatherapy systematic review.

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Brennan, S.E., McDonald, S., Murano, M. et al. Effectiveness of aromatherapy for prevention or treatment of disease, medical or preclinical conditions, and injury: protocol for a systematic review and meta-analysis. Syst Rev 11 , 148 (2022). https://doi.org/10.1186/s13643-022-02015-1

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aromatherapy case study for ptsd

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Ease the symptoms of PTSD with aromatherapy

For centuries people have been using essential oils – natural substances extracted from plants and seeds – to heal the mind and body. The positive effect essential oils can have on us is astounding, and people with post traumatic stress disorder often find that aromatherapy can help them to manage their symptoms. Once you understand how to safely administer essential oils, and have identified oils which provide you with the best results, you might find that aromatherapy offers relief from even the most severe PTSD symptoms.

Essential oils for PTSD symptoms

Lavender is a wonderful essential oil for PTSD because it can help to alleviate fear, anxiety, stress, panic and depression, as well as reduce nightmares and sleep disturbances. Bergamot can relieve anxiety and fear too, and if anger and rage is a symptom you experience, you might find that ylang ylang and clary sage help. Frankincense, chamomile and sandalwood are all also known to improve a variety of PTSD symptoms.

Safety of aromatherapy

Essential oils are incredibly potent, so it’s important to understand the risks associated with them. Generally speaking, they should never be applied directly to the skin unless diluted with another oil, such as sunflower oil.

Try to use high-quality, pure oils where possible, and read the contraindications of each oil carefully before using, because some oils may interact badly with certain medications or be unsuitable for people with certain health conditions. Pregnant women should take particular care to avoid oils which are known to be dangerous to their baby.

If in any doubt, visit a trained aromatherapist to get the benefits of essential oils in a safe environment, rather than using them yourself.

How to use essential oils

To get the benefits of essential oils, you could apply them, in diluted form, directly to your skin. You could add a couple of drops of oil to a moisturising lotion and apply this to your hands and arms each day in order to carry the scent with you.

Many people like to use essential oils in the bath. A few drops into the water is enough to release the beneficial aroma of the oils, and the process of taking a warm, relaxing bath can also help to relieve anxiety or stress.

You could also use essential oils in home diffusers; simply add a couple of drops to the water chamber and allow the oil to be diffused around the home. Alternatively, add essential oils to water in a spray bottle and gently spritz the mixture onto pillows, curtains, cushions, sofas or other soft furnishings.

It’s important to note however, that while choosing your PTSD recovery path you need to address both the symptoms and the underlying condition. NICE guidance from 2005 and 2011 recommends the use of trauma focused psychological treatments for Post Traumatic Stress Disorder in adults, specifically the use of  Eye Movement Desensitisation Reprocessing (EMDR)  and trauma focused  cognitive behavioural therapy (CBT).

Please remember, these aren’t meant to be medical recommendations, but they’re tactics that have worked for others and might work for you, too. Be sure to work with a professional to find the best methods for you.

_________________________________

IMAGE: Neon essential oil diffuser misting on table by  Your Best Digs essential oil diffusers

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Aromatherapy and Essential Oils: A Map of the Evidence

  • PMID: 31851445
  • Bookshelf ID: NBK551017

Background: The purpose of this review is to provide the Veterans Health Administration (VHA) with a broad overview of the effectiveness of aromatherapy and essential oils (EOs), and the health conditions for which these interventions have been examined.

Data Sources and Study Selection: We searched multiple databases through February 2019 for systematic reviews (SRs) of aromatherapy and EOs for health conditions. Using pre-specified inclusion criteria, all abstracts and full-text articles were dual-screened for inclusion. When there were several qualified reviews for the same health condition, we selected a single review based on its recency, methods, scope, and applicability.

Data Abstraction: From each review, we abstracted the focus of the SR, the number of controlled trials included, combined number of participants, duration of trials, condition treated, and relevant findings from controlled trials. We abstracted separate data for each of 5 outcome categories: psychological outcomes, nausea/vomiting, pain and other physical outcomes, sleep outcomes, and global health outcomes.

Data Synthesis: For each review and outcome category we assigned values representing the effectiveness level of the intervention and confidence in the evidence and used these values to generate evidence maps. Additionally, we provide a narrative synthesis of the findings.

Results: We included 26 SRs representing the most recent and comprehensive evidence available. There is moderate-confidence evidence that aromatherapy is beneficial for pain in dysmenorrhea. Aromatherapy is potentially effective for pain in labor/childbirth; blood pressure reduction in hypertension; stress, depression, and sleep in hemodialysis patients; stress in healthy adults; anxiety in perioperative patients; and sleep quality in various populations, with low to moderate confidence in the evidence. For EOs applied topically, there is moderate confidence in the potentially positive effect of tea tree oil for tinea pedis. There is insufficient evidence of efficacy for all other conditions examined.

  • Acknowledgments
  • Executive Summary
  • Introduction
  • Summary and Discussion
  • APPENDIX A. Search Strategies
  • APPENDIX B. Study Selection
  • APPENDIX C. Assessment of Confidence in the Evidence from Systematic Reviews of Aromatherapy and Essential Oils
  • APPENDIX D. Peer Review Comments/Author Responses

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Aromatherapy is the use of essential oils from plants (flowers, herbs, or trees) as a complementary health approach. The essential oils are most often used by inhaling them or by applying a diluted form to the skin. Many essential oils are used in aromatherapy, including those from Roman chamomile, geranium, lavender, tea tree, lemon, ginger, cedarwood, and bergamot.

Aromatherapy is sometimes used for insomnia, but we don’t know whether it’s helpful because little rigorous research has been done on this topic.

Aromatherapy is sometimes incorporated into massage therapy for various conditions, such as knee pain from osteoarthritis or pain, anxiety, and other symptoms in people with cancer.

One study of aromatherapy using two contrasting scents, lemon and lavender, in people under stress found that lemon had a positive effect on mood but neither scent affected stress indicators, biochemical markers of immune system changes, or pain control.

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Anxiety Post-COVID Case Study

Anxiety Post-COVID Case Study

When experiencing anxiety, Aromatherapy provides a method of restoring balance and regaining control.

Bad experiences can leave us emotionally drained, but Aromatherapy gives us an empowering hand by giving us powerful tools for shifting our outlook toward something more positive and beneficial. PTSD can be a difficult and impactful challenge, changing how we manage daily stress. But it doesn't have to define us - Aromatherapy is here as an ally to help us navigate through post-COVID experiences and beyond with renewed resilience. Read more to see how Violet received help from a simple remedy provided by essential oils.

This example is an excerpt from a case study that is part of the experience of our Aromahead Certification Program.

Student: Stacey Client: Violet 34-year-old female who has experienced increased anxiety post-pandemic. Health:  Despite being overall healthy, the client recently endured an unpleasant experience with COVID; now, she is finding her anxiety increasing when close to others and worrying about catching another bout of a viral illness. Blend Intention:  This specially crafted aromatherapy blend seeks to help individuals combat anxiety, bolster immunity, and gain a sense of power. Modality: An inhaler was selected for its ease of use and for keeping the aroma in her personal space. Recipe: Essential oils: 8 drops Sweet Orange Oil  (Citrus sinensis) 6 drops Bergamot Oil (Citrus bergamia) 4 drops Cedarwood Oil (Cedrus atlantica) 1 drop Geranium Oil (Pelargonium x asperum)

Directions: Use it up to five times daily or when feeling anxious for immediate relief.

After experiencing the calming effects of inhaling, our client could assess her fear better and reclaim a sense of control. With continued use of an inhaler that helps bolster their immune system, they feel more capable of addressing concerns about getting sick again. Achieve your aromatherapy certification with a unique case study experience! Gain a greater understanding of essential oils, and learn how to work successfully and comfortably with any client - no matter the situation. Receive expert support  from an assigned Case Study Instructor who will guide you toward success every step of the way.

Gain the knowledge and skills you need to make therapeutically effective essential oil blends! The Aromatherapy Certification Program provides you with the highest-quality aromatherapy education available so you can feel 100% confident in your ability to use your essential oils safely and effectively. You’ll gain the expertise needed to create blends for others – and even transform your career!

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Clinical Aromatherapy

Ashley j. farrar.

a Mayo Clinic Hospital, Apheresis Department, 5777E Mayo Boulevard, Phoenix, AZ 85054, USA

Francisca C. Farrar

b Austin Peay State University, School of Nursing, McCord Building, Clarksville, TN 37043, USA

Clinical aromatherapy is an alternative medicine therapy that can be beneficial in the inpatient or outpatient setting for symptom management for pain, nausea, general well-being, anxiety, depression, stress, and insomnia. It is beneficial for preoperative anxiety, oncology, palliative care, hospice, and end of life. Essential oils can be dangerous and toxic, with some being flammable, causing skin dermatitis, being phototoxic with risk of a chemical burn, or causing oral toxicity or death. The article investigates history, supporting theories, guidelines, plant sources, safety, pathophysiologic responses, and clinical nursing aromatherapy. Recommendations for developing a best practice clinical nursing aromatherapy program are provided.

  • • Aromatherapy is an alternative medicine or integrative therapy that works with conventional medicine treatment.
  • • The Food and Drug Administration of the United States guidelines classify essential oils as cosmetics because they are not drugs for treating or prevention of disease.
  • • Essential oils come from seeds, stems, leaves, needles, petals, flowers, rinds and fruits, woods and resins, roots and rhizomes, and grasses.
  • • Case reports are presented for considerations regarding flammability, elder and child safety, dermatitis, phototoxicity, oral toxicity, and eye safety, including critical analysis and intervention.
  • • Clinical aromatherapy can be beneficial for symptom management for pain, nausea, vomiting, preoperative anxiety, critical care, well-being, anxiety, depression, stress, insomnia, respiratory, dementia, and oncology.

Introduction

The Western perspective on health care has been focused on medications for treatment of health care conditions. It was common for pain to be treated with various levels of opioids and receiving prescriptions for medications with each physician visit. Sadly, over time, opioids and antianxiety medications were abused, with the result of these medications purchased from drug dealers, overdosing, and death. The federal government and states stepped in, passing laws monitoring prescriptions written for opioids; therefore, a search for alternative medicine began. Alternative methods were found in the Eastern perspective on health care. Yoga, Pilates, mindfulness meditation, acupuncture, and scented oils were used with massage. Westerners found many alternative methods to treat medical conditions, such as pain, anxiety, depression, and insomnia, with scented oils from various plant sources. The pendulum began to swing from Western medication to an Eastern holistic approach. Aromatherapy emerged and was embraced as an alternative medicine for many medical conditions. This article investigates the use of clinical aromatherapy. Credibility is seen in the historical evolution and nursing theorist support. Aromatherapy regulation of guidelines, plant sources for aromatic oils, and safe use of essential oils in symptom management in clinical aromatherapy is reviewed. Suggestions are recommended for a best practice model for clinical aromatherapy.

Clinical aromatherapy

Aromatherapy is a fast-growing complementary therapy worldwide. According to the National Institutes of Health National Center for Complementary and Integrative Health, Americans spend more than $30.2 billion annually on this therapy. 1 It is predicted the global market will grow in spending to $5 trillion by 2050. 2 Aromatherapy also is called integrative medicine. 3 It is especially important for frontline nurses to understand the difference between alternative therapy and integrative therapy. In alternative medicine, the therapy works as an addition to conventional medical treatment, whereas integrative therapy is solo and replaces any conventional medical care. The National Institutes of Health National Center for Complementary and Integrative Health developed categories for these therapies—mind-body therapy, biologically based practices, manipulative and body-based practices, energy medicine, and whole medical systems, such as Ayurvedic medicine and traditional Chinese medicine. 3 , 4 Nursing health care aromatherapy falls into the category of mind-body therapy. Nursing health care uses essential oils to complement therapeutic interventions, decrease anxiety. It is expected that the plant-based essential oil applications can be measured, such as a preanxiety symptoms, interventions with essential oil, and postanxiety symptoms. The outcome from the administration of essential oil can be measured with a pre anxiety level and post level of anxiety to determine if the essential oil is effective. 4 , 5

Worldwide historical evolution of aromatherapy

Aromatherapy has been used for thousands of years. Hippocrates, father of modern medicine, advocated the use of aromatherapy due to his belief that aromatic baths and scented massage were key to good health. Essential oils leaders emerged, supporting aromatherapy as a credible therapy for mind, body, and spirit. Table 1 summarizes major historical timelines of countries and cultural influences, validating aromatherapy as medical, clinical, and holistic.

Table 1

Historical evolution

Nursing theorists support for health care aromatherapy

Historical evolution of medical, clinical, and holistic uses of essential oils is embraced by 8 major nursing theorists. Their theoretic frameworks and concepts reflect the use of clinical aromatherapy as a patient-centered and holistic approach for balancing physical health, spiritual needs and well-being. The 8 theorists’ embracement confirms health care aromatherapy is a credible alternative method ( Table 2 ).

Table 2

Nursing theoretic frameworks for health care aromatherapy

Regulation guidelines for essential oils

The Food and Drug Administration (FDA) of the United States guidelines classify essential oils for aromatherapy as cosmetics, because they are not drugs for treating or prevention of a disease. 10 Therefore, aromatherapy essential oils are not regulated by the FDA. The US Consumer Product Safety Commission (CPSC) monitors unsafe products. 11 The CSPC enforces federal laws to protect consumers against unreasonable injury and death from products. 12 The following are examples of how these 2 federal organizations monitor essential oils.

  • 1. Aromatherapy waterless vaporizers and diffusers were recalled due to a defective heater causing a fire multiple times with consumers. The CPSC had the authority to cease the sale of the products and refund consumers. 11
  • 2. The FDA protects consumers from false claims and mislabeled products that mislead the public. Surveillance found Quinessence Aromatherapy Ltd posted on their website advertisement that essential oils protect against and cure coronavirus disease-2019. (COVID-19). This false statement triggered a FDA letter warning to the owner to take the information off their website within 48 hours and cease the sale of essential oil for prevention and cure of COVID-19. These 48 hours included developing a plan to be approved by the COVID-19 Task Force. The company was located in Europe with essential oils sold in the United States. The owner ignored the warning. Due to the fraudulent statement describing essential oils as a curing drug for COVID -19, a second joint letter was sent to the owner by the FDA, CPSC, the secretary of Health and Human Services, and the U.S. Public Health Services ordered the owner of the company to immediately take down the website and cease the sell of essential oils as a curing drug. The company's website was also put on the federal surveillance website list.

Administrators were ordered to cease sale and remove from the Web site immediately. This incidence of a false claim has brought awareness that currently essential oils are complementary therapy and do not treat and/or prevent a disease. Sellers need to be aware of descriptions of aromatherapy and consumers need to know that aromatherapy is complementary. 12

Nurse awareness of essential oils plant sources and uses

Essential oils are used every day for their aromatic scents—for example, perfumes, candles, essential oil plug-ins, scented aerosol sprays for the home, fabric softeners for clothes, hair shampoos, and spices to add flavor to food. Essential oils also are used in over-the-counter herbs and added to medications to add a pleasant flavor to bitter medications. These aromatic essential oils are growing in popularity, with nurses needing to learn about essential oils, their benefits, and safety measures. Essential oils come from seeds, stems, leaves, needles, petals, flowers, rinds and fruits, woods and resins, roots and rhizomes, and grasses. Oil is extracted from the plant by distillation by steam or mechanical cold press. Cher Kaufman, a certified aromatherapist, wrote a book with a series of chapters on plant sources for aromatic essential oils—seeds, petals and flowers, rinds and fruits, woods and resins, roots and rhizomes, and grass. The following is a summary of the plant sources of each category, with examples that could be significant to health care nurses.

Three common examples of essential oils that come from seeds from plants are

  • 1. Cardamom ( Ellettaria cardamomum) —the essential oil is from the plant family Zingiberaceae. Uses for this seed oil include an antibacterial, antifungal, antispasmodic, aphrodisiac, digestive stimulant, expectorant, parasympathetic nervous system stimulant, and stimulant, tonic.
  • 2. Black pepper (Piper nigrum ) is from the plant family Piperaceae. Uses for this oil include an analgesic, antiseptic, antispasmodic, antitoxic, aphrodisiac, digestive, and circulatory tonic; reducing fever reducing pain; as a rubefacient; and for stimulating.
  • 3. Sweet fennel ( Foeniculum vulgare var. dulce ) is from the plant family Apiaceae. Uses for this oil include an anti-inflammatory, antibacterial, antifungal, antispasmodic, detoxifier, and digestive and for relieving gas. 13

Stems, Leaves, and Needles

There are 7 common examples of essential oils derived from stems, leaves, and needles.

  • 1. Cistus ( Cistus ladanifer ) is from the plant family Cistaceae. This essential oil comes from stems, twigs, dried leaves, and dried flowers. Uses for this oil include as a cictrisant or for cell regeneration; as an antibacterial, anti-infectious, antimicrobial, astringent, and antiviral agent; as an immunity booster and regulator; as a tonic and support for parasympathetic and central nervous systems; and for wound healing.
  • 2. Eucalyptus is a tree from the plant family Myrtaceae. It also is referred to by many names, such eucalyptus oil, blue gum oil, blue mallee oil, and gully gum oil. The leaves and twigs are used for burns, wounds, nasal congestion, lowering blood glucose, nasal congestion, and asthma and as a tick repellent. It also is used in medications and supplements.
  • 3. Laurel ( Laurus nobilis ) is from the plant family Lauraceae. This aromatic evergreen scrub is known for its aromatic dark green, glossy leaves. Dried and fresh leaves oil is used as an analgesic, antibacterial, antimicrobial, antiseptic, antispasmodic, and antiviral; for boosting the immune system and calming the nervous system; and as an expectorant and fungicide.
  • 4. Patchouli ( Pogostemon cablin ) comes from the plant family Lamiaceae that is commonly called the mint or dead needle busy herb. Oil from leaves are used as an antidepressant, anti-inflammatory, antimicrobial, antiviral, aphrodisiac, astringent, deodorant, and digestive; for relieving gas soothing the nervous system; and as a stimulant and tonic.
  • 5. Peppermint ( Mentha x piperita L) comes from the plant family Lamiacae in the mint family. Peppermint essential oil is a common flavoring agent in pharmaceuticals, soaps, cosmetics, food, and beverages. This essential is used as an analgesic, antibacterial, anti-inflammatory, antispasmodic, antimicrobial, decongestive, digestive, and expectorant and relieves coughs.
  • 6. Pine ( Pinus sylvestris )—pinus edulis is from the plant family Lamiaceae and from the mint family. Pine essential oil is derived from the needles on the pine tree. The scent is known for the uplifting and positive impact on the mood. It is known for treatment of postsurgery nausea and vomiting. Essential pine oil is used as an analgesic, antibacterial, antibiotic, anti-infectious, anti-inflammatory, antifungal, and antimicrobial agent; assisting in opening lungs and air pathways; as an expectorant; and for soothing nerves.
  • 7. Rosemary ( Rosmarinus officinalis ) is from the plant family Lamiaceae. This aromatic evergreen shrub’s essential oil is derived from leaves, flowers, and stems. This essential oil is known for folk medicine, flavoring food, and herbal tea. Rosemary has been known as a sacred oil. Uses for this essential oil are as an analgesic, anti-inflammatory, anti-infectious, antiseptic, and antispasmodic agent; for breaking up mucus; as a cognitive stimulant, decongestant, expectorant, muscle relaxant (cineole), stimulant, and tonic; and for wound healing (verbenone). 14

Petal and Flowers

There are 8 common essential oils derived from petal and flowers.

  • 1. Clary sage ( Salivia sclarea ) is an herbaceous perennial in the plant family Lamiaceae with a history of petal and flowers used as an herb. The essential oil of clary sage is used in perfumes and muscatel flavoring in wines and liqueur. This essential oil is used as an antidepressant, antifungal, anti-inflammatory, antispasmodic, and aphrodisiac and for calming the nervous system, relaxing the uterus, and stimulating the blood flow.
  • 2. Chamomile (Matricaria chamomilla [ Anthemis nobilis ]) is in the plant family Asteraceae and is a common name for several daisy-like flowers. Chamomile essential oil from flowers is used in herbal tea and is a popular night herbal tea due to the sedative affect. This essential oil is used for support for the nervous system, inflammation, insomnia, menstrual issues, headaches, and skin concerns.
  • 3. Geranium ( Pelargonium x asperum ) and rose ( Pelargonium graveolent )—this essential oil comes from the plant family Geraniaceae. This perennial plant has a sweet floral scent with uses in high-end perfumes and skin products with essentials oils resulting in young radiant skin. Essential oil from the flowers are used for reducing anxiety, as a sedative, for stimulating relaxation, as aids in symptoms from menstruation, as an anti-inflammatory, and for supporting healthy lymph drainage.
  • 4. Jasmine ( Jasminum sambac ; Jasminum grandiflorum )—this essential oil is from the plant family Oleaceae. Jasmine is a genus of shrubs and vines in the olive family. Flowers of this bushy strong-scented perennial plant are used for scent and in tea as a base for green and white teas. As an essential oil, jasmine is used as an antidepressant and aphrodisiac, for calming the nervous system, and as a sexual tonic and stimulant.
  • 5. Lavender ( Lavandula angustifolia ) —this essential oil is in the plant family of Lamiaceae and is a bushy strong-scented perennial plant. Lavender is a popular house décor and frequently used with dried flowers as a complement in weddings. The popular scent is used in balms, salves, and cosmetics. As an essential oil, lavender is used as analgesic, anti-inflammatory, antifungal, and antispasmodic; for calming the nervous system, lowering blood pressure, and reducing anxiety and sensations of pain; as a sedative; and for wound healing.
  • 6. Neroli ( Citrus aurantium var. amara )—this essential oil is in the plant family Rutaceae and is from the bitter orange tree. This essential oil from flowers has a rich floral scent and is known as orange blossom oil. Neroli is used in scented products, such as perfumes and lotions. This essential oil is used as an antidepressant, antifungal, anti-inflammatory, antimicrobial, antioxidant, antiparasitic, antiseptic, and aphrodisiac; for calming; and as a digestive, nervous system stimulant, sedative, and tonic.
  • 7. Rose ( Rosa damascena; R damascena var. alba )—this essential is from the plant family Lamiaceae and is a flowering shrub known as a rosebush. Rose oil is a powerful rich sweet smell. It is used commonly in perfumery. This essential oil is used as an antibacterial, antidepressant, anti-infectious, anti-inflammatory, antiseptic, antiviral, aphrodisiac, and astringent agent; for calming the nervous system and reducing anxiety; as a sedative; as a sexual, general, and uterine tonic; and for wound healing.
  • 8. Ylang-ylang (Cananga odorata )—this essential oil is from the plant family Annonaceae, or custard apple family. This tropical flower is a yellow-shaped flower that grows on the cananga tree. Oil from ylang-ylang is used in cologne, lotion, food flavoring, and soap. This essential oil elevates the mood. Ylang-ylang essential oil is used as an antidepressant, anti-inflammatory, antiparasitic, antispasmodic, and aphrodisiac; for calming the nervous system and lowering blood pressure; and as a sexual tonic. 15

Rinds and Fruits

  • 1. Bergamot ( Citrus bergamia ) is from the plant family Rutaceae. This yellow or green fruit is a hybrid of lemon and bitter orange and has a bitter taste that is more than grapefruit but less than a lemon. The essential oil from the peel or zest of the fruit can cause photosensitivity, with sun exposure causing damage to sun-exposed skin. The essential oil has a citrus fruit smell, with uses in oil perfumes, cosmetics, and scenting food. This essential oil is used as an air purifier, antibacterial, antidepressant, antifungal, anti-inflammatory, and antiviral; for calming; as a deodorant; for digestive regulating (undereating or overeating); for reducing anxiety; as a sedative and tonic; and for wound healing.
  • 2. Lemon ( citrus limonum )—this essential oil is fruit from a small evergreen tree. This oil is from the Rutaceae plant family, with the peel of the fruit and pulp used in culinary and noncultural from lemon essential oil, lemon pie for culinary to cleaning products. The distinct sour taste of lemon is a popular essential oil. The essential oil from lemon is used as an antibacterial, anticoagulant, antidepressant, anti-infectious, anti-inflammatory, antiseptic, antiviral, astringent, antioxidant, and antimicrobial agent; as a digestive stimulant, immunity booster, and lymphatic; and for reducing anxiety.
  • 3. Mandarin ( Citrus reticulata ) —this essential oil is from the Rutaceae plant family. This small citrus tree grows mandarin oranges that are smaller than oranges. A hybrid of the mandarin orange is the tangerine. The mandarin essential oil from peel and rind is sweeter and can be dried for seasoning and used in various food. This essential oil is used as an analgesic, antidepressant, antiseptic, central nervous system tonic, deodorant, digestive tonic, and immunity booster; for reducing reduces anxiety and fevers; and as a sedative.
  • 4. Sweet orange (citrus sinensis )—this essential oil is from the plant family Rutaceae. This sweet citrusy greenish orange fruit oil is from the peel and zest. This oil is used in top perfumes. The leaves are photosensitive but not the fruit. The sweet orange essential oil is used as an analgesic, antidepressant, antibacterial antifungal, antiseptic, antiviral, deodorant, and digestive tonic; for reducing anxiety; as a sedative; for soothing the nervous system; and as a stimulant.
  • 5. Juniper berry ( Juniperus communis )—this purple-black berry is a female evergreen cone. This essential oil is from the plant family Cupressaceae, derived from conifers, and often is used as a spice. The essential oil is used as an analgesic, antiseptic, antiseborrheic, anti-inflammatory, antifungal, antiviral, decongestant, and detoxifier and for increasing circulation and reducing fever. 16

Woods and Resins

  • 1. Cedarwood ( Cedrus atlanticia )—cedarwood is from the plant family Pinaceae and the needles, leaves, bark, and wood are for extracting the essential oil. The evergreen conifers have a soothing woodsy scent. The essential oil is used as an antifungal, antiseptic, and astringent; for breaking up mucus; and as a calmative, insect repellent, lymphatic decongestant, and general tonic.
  • 2. Frankincense ( Boswellia carteri )—this essential oil is in the plant family of Burseraceae and is from a Boswellia tree. Resin that is a hardened gumlike material is used in aromatic incense and perfumes. The essential oil is used as an analgesic, antibacterial, antidepressant, anti-infectious, antimicrobial, and astringent agent; for immunity tonic; for reducing anxiety; as a sedative; and for soothing the nervous system and wound healing.
  • 3. Sandalwood ( Santalum album )—this essential oil is from the plant family Santalaceae. The oil is extracted from wood, heartwood of the trunk, and sawdust. The essential oil from sandalwood is used in medications, skin beauty treatment, incense sticks, perfumes, mouthwashes, deodorants, and antiseptics. As an essential oil, it is used as an antibacterial, antidepressant, anti-inflammatory, antimicrobial, antiviral, aphrodisiac, and sedative; for soothing the soothes nervous system; and as a general tonic. 17

Roots and Rhizomes

  • 1. Ginger (Zingiber officinale ) is distilled from the rhizome or underground stem of a root of the herb zingiber. Ginger also is known as the oil of empowerment for the feeling of confidence. Ginger root oil is a frequently used spice. In addition, this dried and ugly root is used as an analgesic, antibacterial, antispasmodic, digestive support, immunity harmonizer, and rubefacient.
  • 2. Vetiver ( Vetiveria zizanoides ) is derived from the aromatic roots and also called khus oil. It is derived from the vetiver plant that is a clumpy, green grass that can grow 5 feet or more. This essential oil is used as an antiseptic, antispasmodic, anti-inflammatory, digestive stimulant, immunity booster, and sedative, and for skin support and soothing the nervous system. 18
  • 1. Lemongrass ( Cymbopogon citratus ) is an essential oil that comes from the leaves and stalk of the lemongrass plant. This grassy plant is used in cooking and herbal tea. The oil from the grass has a lemony powerful scent and is bright or pale yellow. This essential oil is used as an analgesic, antidepressant, antiviral, immunity booster, and general tonic.
  • 2. Palmarosa ( Cymbopogon martinii var. motia ) is an essential oil that comes from a tall herbaceous grass and can be called Indian geranium or rose oil. The oil has a sweet citrus lemony scent that has a yellow color. 19

Administration of essential oils

There are 4 basic methods for administration of essential oils. Nursing commonly uses topical skin application of essential oil for administration. If a facility has an integrative medicine department, massage therapy usually includes an essential oil. The following is an overview of the 4 methods by which essential oils are absorbed.

  • 1. Topical application with skin absorption of the essential oil. Examples include massage, scented bath, cosmetics, and perfumes.
  • 2. Absorption of the essential oil by inhaling in nostrils. Examples include direct inhalation via diffuser with steam, aroma stones, and oil-scented strip of cloth. Indirect absorption examples include scented room spray and heated candle wax, detergent, and bathroom and floor cleaners.
  • 3. Oral absorption of the essential oil. Examples include gelatin capsules and safe dose of essential oil diluted.
  • 4. Internal absorption of essential oil. Examples include scented mouthwash and scented suppository or vagina douche. Essential oil used for flavor in prescription medications and herbal medicines. 20 , 21 , 22

Pathophysiologic response to health care aromatherapy

When essential oil in aromatherapy is inhaled, molecules activate the olfactory, respiratory, gastrointestinal, and/or integumentary systems based on the pathway of activation. These molecules are capable of releasing neurotransmitters, such as endorphins, to trigger a sense of well-being and an analgesic effect. 20 , 21 There are 2 common pathways triggering a pathophysiologic response to aromatherapy molecules. The most common pathway is inhalation, such as by a diffuser. Activation of olfactory stimulation produces immediate change in parameters for blood pressure, pulse rate, muscle tension, pupil dilation, body temperature, and blood flow. 20 , 21 The following summarizes this pathway:

  • • The olfactory stimulation by aromatherapy travels via nostrils to the olfactory bulb.
  • • The stimulus then travels to the brain for processing, where the amygdala triggers an emotional response and the hippocampus retrieves and/or forms memories.
  • • The limbic system interacts with the cerebral cortex, activating thoughts and feelings.
  • • The inhaled aromatherapy molecules travel to the upper respiratory tract and then to the lower respiratory tract.
  • • Molecules than travel to the pulmonary blood vessels to the blood stream then to organs and tissues. 20 , 21
  • • In summary, the inhaled aromatherapy molecules affect mind, body, and spirit.

The second common pathway is through the skin, such as by a massage, in which molecules are absorbed through the skin. The pathway is summarized:

  • • The molecules travel to the upper respiratory track and then the lower respiratory tract.
  • • Molecules then travel to the pulmonary blood vessels, to the blood stream, and then to organs and tissues. 20 , 21
  • • The skin pathway can activate olfactory stimulation and also activates application of scented oil to the skin pathway triggering a mental and physiological response.
  • • The skin pathway absorption of essential oils can reduce a patient’s perceived stress, enhance healing, and increase communication. 20

Safe use of essential oils

Coming home from a long challenging day of work to the aromatic smell of a favorite essential oil can immediately decrease the stress from a busy and challenging day. Relaxing in a scented uplifting bubble bath can make someone feel like a new person. On the flip side, aromatic essential oils can be toxic, causing chemical burns and even death. Aromatherapy is growing in usage and can be extremely dangerous if not used safely because of a knowledge deficit. Two ethical principles apply to nurses when administering essential oils. The first is beneficence, in which the nurse takes positive steps to prevent harm. The second ethical principle is nonmaleficence, which means having an obligation to do no harm to a patient. Legal consequences could result if harm to a patient occurs due to negligence from administering of aromatherapy. Therefore, the bottom line is the need for nurses to learn about aromatherapy essential oils and their potential harms, such as poison and lethal complication. The following case reports portray safety considerations, complications, and interventions.

Combustion Reaction Safety

TF is a 54-year-old man who lives in Phoenix, Arizona; he is an advocate of essential oils and frequently uses them for anxiety and to promote sleep. On his day off, TF has several errands, including his monthly supply of essential oils. His first errand was to purchase essential oils. During his last errand, TF heard his name being called by an old friend. TF sat down to visit with his friend for a few minutes; the visit lasted 45 minutes. When TF returned to his car, he found black smoke in the car and a large burnt hole in his backseat where his purchased essential oils were placed. TF called the police to file a report.

Critical analysis revealed the large supply of essential oils were stored in the back seat. TF left the oils in the car for 45 minutes with the outside temperature of 112°F, with the potential increase in the temperature in the car increasing to 160°F. The essential oils caught on fire, resulting in the smoke and burnt hole in the backseat of the car.

Intervention for this unsafe use of essential oil is education that these oils are flammable and need to be stored in a cool dark place in the original bottle, which is colored to prevent direct sunlight penetrating to the essential oil. Unsafe storage by leaving essential oils in a hot car can cause a combustion reaction, triggering flames and a fire.

Elder and Child Safety

CF, a 66-year-old woman, was admitted for inpatient treatment of sepsis from an acute urinary infection. At night she can become agitated and screamed that snakes were crawling up her wall. The provider ordered aromatherapy and increased lighting in the room. Turning on a bed alarm and increased rounding also were ordered. The nurse brought the aromatherapy essential oil to the room and left to get a steam diffuser. When the nurse returned, CF appeared drunk. The nurse found the bottle open on the bedside table. The nurse called for assistance.

Critical analysis revealed the nurse left the bottle of essential oil on the nightstand unattended when she left the room. The patient was able to open the bottle and drink a small amount of the essential oil, causing the drunken behavior.

Intervention for essential oil left attended with a confused elderly patient was administration of milk to dilute the essential oil. The provider was called for further orders and an incident report was completed. The elderly and children are vulnerable to adverse effects from inappropriate use of essential oils. Early recognition is appearing drunk. Essential oils should be locked in a container in a hospital and kept away from elders and children. An essential oil bottle should not be left unattended, especially with this confused patient with delusions. The diffuser with the essential oil needs to be prepared outside of the patient’s room. 11

Allergic Contact Dermatitis and Primary Contact Dermatitis

TA, a 30-year-old woman, works at a massage therapist and is extremely popular. Bookings must be in advance because her schedule stays full. Each day she works 8 hours to 9 hours, with mostly 1.5-hour massages. She uses a lotion with an aromatic essential oil. After 3 months, she developed a bright bred rash on her hands and lower arms. She used a steroid cream on the rash without resolving the rash. Over the next month, the rash got worse. TA scheduled an appointment with a dermatologist.

Critical analysis evaluated allergic contact dermatitis versus primary contact dermatitis. In allergic contact dermatitis, the allergy occurs over a period whereas primary contact dermatitis occurs the first time the essential oil is used. In allergic contact dermatitis, the symptoms are a bright red rash that worsens with time whereas the primary contact dermatitis a presents as a red wheal or burn. 20 , 23

Intervention was based on treating allergic contact dermatitis based on symptomatology and length of time. Patch testing revealed the specific essential oil to stop using, allowing her to continue as a massage therapist. If TA had primary contact dermatitis, the red wheal or burn area from the toxic oil would be diluted with vegetable oil or milk then washed with unscented soap. 23

Essential Oil Phototoxicity

AJ is a 34-year-old woman who loves the sun. She lives in an apartment with a swimming pool. The average summer temperature is 102°F. On weekends she can be found at the swimming pool for 4 hours per weekend day. AJ’s pool relaxing is 4 hours to 5 hours per day. She sets an alarm hourly to turn from back to stomach. AJ says the sunrays lift her up and gives her a beautiful brown tan with sunscreen oil. Due to the shutdown of her state due to COVID-19 and stores closed, AJ decided to shop online for home delivery of essential oils. AJ found a Web site with a sale on essential oils that had a pop-up advertisement declaring breaking news that essential oils prevent and cure the COVID-19 virus. AJ purchased several citrus fruit essential oils. AJ applied a mandarin essential oil to her neck and chest to ward off the COVID-19 virus. AJ left the pool early because of a burning sensation on her neck and chest. She took a shower and noticed several burned areas. The next day, the red burned areas turned to a brown skin damage appearance unlike any sunburn she ever experienced. AJ scheduled a dermatologist appointment due to the discoloration and discomfort not resolving. 16 , 20 , 23

Critical analysis revealed that AJ was scammed by a fraudulent online statement to sell essential oils in a pandemic COVID-19 fearful time. The mandarin essential oil was not diluted when applied to the skin, increasing the risk for dermal toxicity. The pure mandarin essential oil was phototoxic and inflected damage to the skin, resulting in dark pigmented skin that could be permanent. 16 , 23 Dermal toxicity also occurred with the essential oil not being diluted. The regular sunburn resulted in redness and blisters on her skin. AJ scheduled an urgent dermatology appointment. She used an over-the-counter steroid cream for pain relief.

The intervention to stop using the phototoxic essential oil and seek a specialist, which AJ did, with scheduling the dermatology appointment. The essential oil label always should be read for safety instructions. If a photosensitivity essential oil is used, wait a minimum of 12 hours before exposure to sun ultraviolet radiation. AJ should consult a qualified aromatherapist who has training for aromatherapy, not a seller of essential oils, to prevent harm from essential oils. A registry database for trained aromatherapists who have passed the core level of aromatherapy examination can be found at t https://www.aromatherapycouncil.org.uk/about_us 10 Essential oils always should be diluted in a carrier oil. A carrier oil prevents irritation to the skin and side effects of the essential oil. Examples of carrier oils include coconut oil, coconut oil, aloe vera gel, unscented lotion, vegetable oil, and avocado oil. Because oil and water do not mix, milk is used to remove the oil and calm the skin followed by washing of the skin by unscented soap. 23

Phototoxic essential oil contains constituents that triggers a chemical process that changes the skin DNA, making the skin susceptible to sun ultraviolet radiation. This chemical change in the skin is called photosensitivity and the primary constituent is confurocoumarins that causes phototoxic reaction. Exposure of the applied photosensitivity essential oil to ultraviolet radiation from the sun inflicts skin damage with darkly pigmented skin that can be permanent due to the long period of exposure to sun ultraviolet radiation. 23 It is extremely important to determine if an essential oil is phototoxic. AJ should find this warning on the label of the essential oil. Essential oils are not regulated by the FDA but the FDA monitors Web sites for fraudulent postings. AJ should report the online site and harm to her skin to the FDA for investigation. 11

Oral Toxicity

LM, a 110-pounds 20-year-old woman who lived with her mother, was told by an essential oil seller that she heard essential oils could prevent and cure COVID-19. LM was terrified that she could contract the virus with a resurgence of COVID-19 later in the year. LM was extremely excited about this information and asked which essential oil she should use orally to protect herself from this deadly pandemic COVID-19 virus. The seller recommended a safe dose for eucalyptus essential oil twice weekly orally. After a week LM decided to increase the oral dose to ward off the COVID-19 virus. She decided to drink half of an 8 oz glass of eucalyptus essential oil. Within 10 minutes she experienced burning in her throat, mouth, and stomach. 23 LM yelled for her mother to come quickly. The mother found the daughter vomiting, staggering, and with slurred speech. The mother found the eucalyptus essential oil bottle and a glass indicating she had drunk eucalyptus essential oil. The mother called 911 with the dispatcher sending an ambulance and notifying the Poison Control Center for eucalyptus poisoning.

Critical analysis of oral toxicity of eucalyptus revealed LM had drunk an unsafe dose causing poisoning with central nervous system depression and a chemical burn in her mouth, throat, and stomach. LM was admitted to the intensive care unit.

Intervention was police investigation of the fraudulent information that eucalyptus could prevent and cure COVID-19 information by the seller of the essential oil with unintentional poisoning LM. A qualified aromatherapist that is certified or completed aromatherapy curriculum. Don't take advise from a seller of essential oils without expertise. Seek consultation for safe use of essential oils. 11 Even with a safe oral dose of eucalyptus can cause harm. Safe use of essential oils is to not take essential oils internally. It is extremely important that induced vomiting is not done for this toxicity.

Oral toxicity symptoms are rapid decline with complaint of burning in the mouth and throat and abdominal pain. Central nervous symptoms are ataxia and respiratory depression, and, with a higher dose, possible nasal intubation is needed for mechanical ventilation and deep coma. Death can occur with a toxic dose. 20 , 23

MF accidently splashed essential oil in an eye when she was preparing essential oil for a diffuser. Her eye was burning and painful and her vision blurred in the eye.

Critical analysis reveals essential oils are toxic to eyes and can result in a chemical burn. The eye should be rapidly irrigated with milk or a vegetable oil carrier. A washcloth or cotton ball can help with the irrigation. After treatment flush the eye with water. Do not flush the eye with water initially due to oil and water not mixing.

Aromatherapy clinical management

Clinical nursing aromatherapy is patient symptom management with measuring the outcome in a clinical setting. When aromatherapy is ordered by a provider for symptom management, a nurse needs to perform a history assessment, obtain vital signs, identify the symptom, educate the patient, measure symptom management, evaluate the effectiveness, and document the plan of care. 1 , 6 , 7 , 24 The following is an overview of clinical management of the essential oil:

  • • Allergy—inhalant, skin, food, and medication allergy or sensitivity. Consider the need for a patch test.
  • • Chronic conditions—assess condition that could be impacted by aromatherapy, such as plant source triggering asthma attack or cancer that is fed by estrogen, with a few essential oils having estrogenic activity.
  • • Obtain vital signs—assess if there is a problem proceeding with essential oil administration.
  • • Symptoms needing to be managed—such as anxiety, depression, insomnia, nausea, and pain
  • • Educate the patient about the essential oil, procedure, safety, symptom management, patient-centered selection of the essential oil, and consent for implementation.
  • • Outcome measurement of symptom relief—select a tool for measuring the symptom, such as pain. The pain tool could be measurement of pain from 1 to 10 or visual picture rating of pain; or, a nonverbal patient’s pain could be measured with a visual picture range, and pain in a patient unable to communicate could be measured with physiologic changes, such as vital signs, guarding of the area, and facial grimaces from discomfort. After selection of the pain measurement tool, rate the presymptom range, and post-implementation, measure at end of post symptom score for a change in outcome findings.
  • • Evaluate the effectiveness of the essential oil on the symptom. The outcome goals are decrease in the symptom and increased well-being and quality of life. Patient-centered symptom management and presence of a nurse could increase patient satisfaction.
  • • Document the procedure and incorporate into the plan of care.
  • • Examples of clinical conditions and settings that can benefit in the management of symptoms in the inpatient and outpatient settings are pain, nausea and vomiting, preoperative anxiety, critical care, general well-being, anxiety, depression, stress, insomnia, respiratory, dementia, oncology, palliative care, hospice, and end of life. 1 , 6 , 7 , 24

Best practice model for clinical symptom management

Aromatherapy is used as an alternative medicine and complement to traditional care. Aromatherapy is rising in popularity and is a cost-effective symptom manager. The following are suggested steps for guidance and triggers for brainstorming to develop a customized patient-centered symptom management program using essential oils in an inpatient or outpatient setting.

  • 1. Buy-in from major stakeholders. Develop a committee that includes interprofessional members. Input from all stakeholders, including frontline nurses, needs to be embraced; and, commit, by a recorded vote, to proceeding with the aromatherapy program.
  • 2. Develop a policy and procedure manual. Search the literature for best practice aromatherapy models. If possible, contact the facility for assistance with the startup of the program. For example, a best practice model is at the Mayo Clinic in Phoenix Arizona. This research and education facility uses aromatherapy for alternative medicine and has integrative medicine.
  • 3. Upon approval, establish guidelines for safe and effective implementation, including infection control, safe storage, and disposal of the chemical oil.
  • 4. Identify common symptoms that could occur in the facility, such as pain, anxiety, depression, nausea, and insomnia.
  • 5. Identify nursing considerations, such as assessment, chronic illness, administration, and safety.
  • 6. Identify preoutcome and postoutcome measurements and best tools for measurement. For example, anxiety is a symptom: identify a pretest and post-test to measure anxiety that is a short tool.
  • 7. Identify and educate aromatherapy champions to lead the new program by supervising and mentoring nurses, for example, a classroom course for hospital nurses and a certified clinical aromatherapy practitioner course.
  • 8. Evaluate the data from the pre-intervention and post-intervention of aromatherapy. Interpret the findings and refine if needed.
  • 9. Data analysis to justify aromatherapy is an effective intervention for symptom management.
  • 10. Seek a provider standing order for aromatherapy for sustainability. 1 , 24

Aromatic scents and oils used in clinical aromatherapy can be beneficial for symptom management such as pain, nausea, vomiting, anxiety, depression, stress, insomnia, agitation with dementia, cancer pain, and end of life symptoms, Clinical aromatherapy has been found beneficial in the inpatient and outpatient settings especially critical care, oncology, palliative care, hospice, and surgical. On the flip side, aromatic essential oils can be dangerous and toxic due to certain oils being flammable, causing skin dermatitis, or being phototoxic, with risks of chemical burn, oral toxicity, and even death. Therefore, it is important that nurses learn about essential oils. If a facility has a clinical aromatherapy program, it is critical that frontline nurses be educated with a classroom course on essential oils. Champions need to be selected for a clinical aromatherapy practitioner course. These certified aromatherapists can lead the program, serve as consultants, and mentor nurses.

A.J. Farrar and F.C. Farrar have no commercial or financial conflicts of interest or any funding sources.

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Case Study: Aromatherapy in Long-Term Care

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I journeyed into the mainstream healthcare system in 2013.  At the time utilizing aromatherapy as a non-pharmacological option in senior care was rare.  However, evidence was emerging to support its efficacy and I happened upon an opportunity to put my essential oils to the test.

I began working with an ambitious and compassionate director of nursing (DON) for a large long-term care center in Minnesota.  She was interested in using essential oils and blends with their population. They had already attempted some aromatherapy on their own but with mixed results.  A full floor was devoted to memory care residents.  Several residents had advanced Alzheimer’s disease and dementia, exhibiting extreme symptoms that were not responding well to the current medication protocols.

After a discussion with the DON, we concluded we would address anxiety, mood, sleep, focus and appetite. We also addressed cravings for an alcoholic and an unique issue for a WWII survivor.  We replaced their collection of “aromatherapy” (which ranged from synthetic lavender-scented Febreeze and lotion to low quality essential oils purchased from the local grocery store) with the premium therapeutic essential oils I source for my brands.  The following are just some of the findings from these trials.  I want to emphasize that while these were simple in-house studies for internal use and were not set up according academic or clinical research standards, they still held immense value.

Anxiety Trial: 

A male resident was experiencing agitation, up at night walking, calling out, and even becoming violent at times.  He was not responding well to pharmaceutical intervention and staff became concerned the medications were making him worse.  They wanted avoid relying on pharmaceuticals if possible.

aromatherapy case study for ptsd

A chart was created to track resident behavior.  Behaviors were scaled from 0-10 both before and after aromatic intervention, with a “10” being the worst.  Essential oil/blend and method of application were also recorded.  We found the following:

The most common method of application was via inhalation.  The resident was violent and reactive on several occasions and staff considered him a level 10.  During each recorded incident he was successfully calmed after inhalation of our essential oil blend.  Results were consistent for this gentleman and staff was able to avoid the use anti-anxiety/antipsychotic pharmaceuticals. Within several weeks he hardly needed the medications.  No side effects were reported from the intervention and the staff felt comfortable administering the aromatherapy.

Alcohol Cravings

A gentleman with a history of alcoholism was struggling with his transition into long-term care.  He was craving a drink and would exhibit anxious behaviors.    In his case, I addressed both the neurological element of addiction and the aroma of the blend.  My goal was to mimic the flavor and effect of his favorite drink. This gentleman loved rum and cokes.  I blended sweet, spice and vanilla notes with essential oils that were sedative, emotionally balancing and somewhat euphoric.  He was provided an inhaler and instructed to use it when he felt a craving.  The gentlemen reported that he like the blend and felt it helped him.  Staff reported the gentleman would calm down and was better cope with the transition.

WWII Survivor

An elderly woman was admitted into the transitional care unit to recover after a surgery.  She was having a difficult time sleeping at night, experiencing symptoms of PTSD including hallucinations and flash backs from World War II.  She was also diagnosed with post-operative delirium.  The DON was concerned because she was not improving and further medicating was adding to the problem.

In this case I wanted to address her physical pain, her emotional/spiritual state  and support deep, quality sleep.  The blend included powerful anti-inflammatory essential oils, sedatives and those aromatics historically known for their spiritual significance.  I instructed staff to dilute the blend and massage it into her feet and legs, while avoiding her incision site on the knee.  The DON called me back after a week of use and said: “Whatever you made, it’s working – and we need more!” This patient’s delirium was calmed, her perception of pain reduced and her sleep improved.  She was able to return to a normal sleep/wake cycle and better participate in her recovery from surgery.

Other Positive Results

There is always more than meets the eye during an aromatic intervention.  Those working directly with patients often feel helpless when traditional interventions do not work and/or produce more challenges due to negative side-effects. When a simple and non-invasive solution is available to staff, they feel empowered and their stress level is reduced. Having a safe non-pharmaceutical alternative that works without producing side effects allows them to feel more confident and successful in their jobs.

Staff can enjoy the benefits of aromatherapy also.  They might use a stimulating blend to perk up during a long shift, take a whiff of their favorite essential oil when unpleasant odors are present, or take advantage of natural anxiety relief when they are having a bad day.  They can even relieve debilitating headaches and find relief when feeling under the weather.

In each situation, aromatherapy not only reduced the patient’s symptoms but it also reduced or eliminated the challenges associated with pharmaceuticals (ie: side effects, waiting for them to begin working, wearing off before they can be re-administered).  Because the blends are expertly formulated with high quality essential oils, they are safe to use alongside pharmaceuticals.  Since aromatherapy is inhaled it directly impacts the brain through the olfactory nerve. Improvement is observed much faster than waiting for a drug that is administered orally to kick in.

We even found the need for a drug was often avoided when aromatherapy was used.  The reduced reliance on pharmaceuticals proved to be an invaluable benefit considering now there is stronger regulation in place regarding the use of anti-psychotic and anti-anxiety medications and certain pain relievers.  In fact, today the Centers for Medicaid Services require non-pharmaceutical options be utilized in long-term care.  Aromatherapy turned out to be the perfect solution.

Perhaps the most important benefit to note is that each resident received tailored care that was gentle, holistic and person-centered without being a major strain on resources or time.  Staff simply selected the oil that matched the symptom and administered without the need for a prescription.

The pleasurable impact of aromatherapy quickly reaches the body, mind and soul in a unique and nurturing way. As demand for natural alternatives grow among all consumers today, so does the demand for such care among the aging population as they approach their last stages of life. As we move into the future we will continue to expect long-term care that embraces the needs of the whole person over simply treating their symptoms with medication, as we have seen in the past.

Although these were not official studies, they produced the initial evidence to support my ongoing research and formed the foundation for what I do today.  In this case, we used our findings to gain financial support from stakeholders and build a full aromatherapy program for this particular nursing home.  We have since expanded my program into their entire health system including assisted living, memory care, and transitional care and they are seeing amazing results.  I am proud to see aromatherapy becoming one of the hottest topics in medical literature and know I have been a part of transforming the way we help people age.

aromatherapy case study for ptsd

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Roland Bal | Resolving Trauma and PTSD

Case Studies PTSD and Post-Traumatic Stress Disorder

Written by Roland Bal

These case studies of PTSD are mostly from people I have worked with over the years, with some fictitious elements added or parts omitted, simply to highlight the mechanisms and dissociation processes of trauma.

- Surgery - Car accident - Rape - Falling accident - Grief/Bereavement - Birth/cesarean

Case Study PTSD #1: Surgery

I’d consider surgery to be one of the medical wonders of this day and age. Unfortunately, as with many things, it has become big business. Rather than being carefully skeptical and hesitant about surgery, it has become the norm to undergo it, in some countries at least, even for minor issues that can easily be treated by non-invasive therapies.

John is a middle-aged man who recently went through an open-heart bypass procedure. Full anesthetic was administered, and the operation itself went well. From John’s perspective, however, it is a different story. Towards the end of the operation, John’s anesthetic started to wear off. Although he wasn't able to feel physical pain, he did regain consciousness. The last 20 minutes of the operation, when they cleaned and stitched him up, he went through agony. John didn't experience pain, but was overwhelmed by feelings of helplessness as he was unable to move or let the medical staff know that he had become conscious.

The experience left him traumatized. Subsequently, his sleep was severely disturbed with repeated flashbacks of the alarming "wake up" during surgery. His blood pressure remained high. He was very snappy, agitated, and irritated. When asked about it, he admitted that he was very angry with the medical staff for not acknowledging that something like this could happen, and for not administering the right dose of anesthetic. His wife said that sadly, John is not the same man that he used to be.

Case Study PTSD #2: Car Accident

Ella is in her thirties, ambitious and active in life. On a wintry evening, while driving back home from work, she lost control of her car while negotiating a bend in the road. The car spun and came to a halt after it crashed into a tree. She was taken to the hospital, unconscious, with fractured ribs, a torn spleen, and concussion. Ella had no memory of the event after losing control of the car; however, months after the accident and her release from the hospital, she suffered from anxiety and fatigue accompanied by chronic pain. She managed to work only part time, but forced herself to drive again.

Case Study PTSD #3: Rape

Jane is married and has two children. Outwardly they seem to be a happy, normal family. She sought treatment as she had frequent outbursts of anger, often for little things and against her children. She also had difficulties with intimate contact with her husband, and always needed some kind of background noise, like music or television, or some kind of occupation. As we progressed in our work, it came to light that Jane was raped by a friend of the family at a young age. Her shame and pain about what happened was covered up by anger, which expressed itself in her family surroundings.

Case Study PTSD #4: Falling Accident

Doug fell in the basement after having a verbal fight with his partner. Though he didn't hurt his head, he’d hurt his back and the stiffness and dull pain didn't go away even though it had been there for some time now. He continued to take prescription drugs for pain and inflammation, which upset his digestion and made him feel nausea from time to time. He angrily blamed himself for losing his footing. This is a clear case where the anger of an argument was coupled with and projected onto the fall, and was then internalized through self-reproach. The persistence of back pain turned out to be the psychosomatic holding on to anger. Although Doug didn't suffer the usual PTSD symptoms, this is still a post-traumatic stress condition!

Case Study PTSD #5: Grief/Bereavement

Karen lost her son in a motorcycle accident. She’s retired, widowed, and lived on her own. She smoked heavily, suffered from insomnia, and admitted that she was overcome by grief, and often felt lonely and depressed. She was able to positively identify that her condition was related to the death of her son, but was not able to let go of her attachment to him.

Case Study PTSD #6: Cesarean Birth

Kelly initially visited me to let me have a look at her little girl, who was just a few weeks old. She was very concerned because the baby cried herself to exhaustion before succumbing to sleep. Doing the routine intake/checklist questions I discovered that the birth had been anything but normal, and had turned into an emergency cesarean.

The pregnancy had gone very well with the baby in the right position. Karen was taken to the hospital once the contractions had started. After some hours of labor, with very little cervix dilation, the doctor opted for emergency cesarean surgery, as the baby had descended and it had been stuck for too long with the head in the base of the mother’s pelvis. Kelly and her husband had no time to take in and consider the situation, and went along with the decision of the doctor.

Dealing with Helplessness

Looking back, Karen realized that she felt out of control and overwhelmed by the suddenness of the changed circumstances. She was severely frustrated with how things turned out, and felt angry with the medical staff. Rationally, she understood that the doctor did the right thing. Emotionally, she felt a sense of helplessness for having had to give in to the "rules" of surgery and medical practice. Finally, what emerged was that she had trouble accepting her child due to her desire for a natural birth; again, the anger and resentment towards the medical intervention were masking her sense of helplessness, and her frustration was coupled with and projected onto her non-acceptance of the child, which resulted in the crying and misery of the little one.

  • Do you want to reduce anxiety, hyper-vigilance, and being “ON” alert constantly?
  • Do you want to move out of a dissociated, fatigued and depressed state?
  • Do you want to work with anger and reestablishing boundaries?
  • Are you interested in sleeping better, having better relationships, and being able to live a normal life?

I have created The Trauma Care Audio Guided Meditations which address the most fundamental insights into the processes of trauma and dissociation and how you can work through them.

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Oh man, that last one with the birth process changed.

This makes me wonder how differently my own mother treated me, as I was her first kid after a miscarriage.

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rape was down to a T .. as im sure the others

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  1. PDF Aromatherapy for Posttraumatic Stress Sufferers and Their Caretakers

    Essential oils can be used alone or in blends. Any of the oils above can be used either way. Personal preference and therapeutic property are the main criteria when choosing an oil. The most common ways to use aromatherapy for PTSD are inhalation, topically, and baths (La Torre, 2003). There are standard precautions to follow for all essential ...

  2. PDF The Use of Bergamot Essential Oil for PTSD Symptomology: A Qualitative

    Bergamot essential oil was chosen for this research study. Bergamot is a citrus fruit whose essential oil coming from the rind, is high in linalyl acetate and linalool, known for their calming effects via its ability to alleviate the symptoms of physical and psychological stress (Liu et al., 2013). Bergamot also contains a chemical constituent ...

  3. The Use of Bergamot Essential Oil for PTSD Symptomology: A Qualitative

    This qualitative phenomenological study sought to understand the impact of aromatherapy from Bergamot essential oil on managing PTSD symptomology. A two-week pilot study was conducted consisting of 12 first responder, medical, firefighter and military men and women presenting with symptoms of PTSD in San Diego, California.

  4. Therapeutic Effect and Mechanisms of Essential Oils in Mood Disorders

    2. Therapeutic Effects of EOs. Our previous studies have shown EOs to be effective in alleviating symptoms of depression, anxiety, and stress in adults both below and over 60 years of age, respectively [9,10].Table 1 summarises the effect of EOs in human studies. For instance, the inhalation of lavender and chamomile EOs was found to decrease levels of depression, anxiety, and stress in older ...

  5. Aromatherapy through the lens of trauma-informed care ...

    Select an essential oil that brings a feeling of safety and calm. 2. Sit comfortably or stand with your back supported. 3. Take one teaspoon or 5 ml of a carrier (e.g., jojoba, sunflower or sweet almond oil, unscented lotion). Add 1-2 drops of your essential oil to the carrier and blend them together. Place the blend into the palm of your ...

  6. The Use of Bergamot Essential Oil for PTSD Symptomology ...

    This qualitative phenomenological study sought to understand the impact of aromatherapy from Bergamot essential oil on managing PTSD symptomology. A two-week pilot study was conducted consisting ...

  7. The Effectiveness of Aromatherapy for Depressive Symptoms: A Systematic

    In case of doubt to include any study in the second screening, the full article was reviewed. Two independent authors carried out the search and selection of relevant studies for the present review. ... The essential oils used in the other studies comprise lavender, a mixture of 2-4 different essential oils, and rose otto combined with ...

  8. (PDF) Potential use of Essential Oils in prevention and management of PTSD

    Using essential oils or their commercially available blends can reduce the symptoms of anxiety, depression, mood swings, insomnia and other conditions caused by PTSD. There is a strong trend ...

  9. The Effects of Aromatherapy on Anxiety and Depression in People With

    Introduction. People with cancer may experience a variety of physical and psychological symptoms (1-3).Anxiety and depression are relatively common and have negative effects on the quality of life (4, 5).The patients with untreated anxiety or depression are less likely to take treatment medications, or may withdraw from family or other social support systems (6-9).

  10. Orange essential oil may improve symptoms of PTSD, say researchers

    Post-traumatic stress disorder affects around 8 million adults in the United States, but treatments for the condition are still limited. Orange essential oil may offer a nonpharmaceutical option ...

  11. Effectiveness of aromatherapy for prevention or treatment of disease

    Aromatherapy — the therapeutic use of essential oils from plants (flowers, herbs or trees) to treat ill health and promote physical, emotional and spiritual well-being — is one of the most widely used natural therapies reported by consumers in Western countries. The Australian Government Department of Health (via the National Health and Medical Research Council) has commissioned a suite of ...

  12. Ease the symptoms of PTSD with aromatherapy

    Essential oils for PTSD symptoms. Lavender is a wonderful essential oil for PTSD because it can help to alleviate fear, anxiety, stress, panic and depression, as well as reduce nightmares and sleep disturbances. Bergamot can relieve anxiety and fear too, and if anger and rage is a symptom you experience, you might find that ylang ylang and ...

  13. Aromatherapy and Essential Oils: A Map of the Evidence

    Background: The purpose of this review is to provide the Veterans Health Administration (VHA) with a broad overview of the effectiveness of aromatherapy and essential oils (EOs), and the health conditions for which these interventions have been examined. Data Sources and Study Selection: We searched multiple databases through February 2019 for systematic reviews (SRs) of aromatherapy and EOs ...

  14. (PDF) Aromatherapy, Olfaction, and Spatiotemporal Interactions

    Conclusion: The possible peripheral edema reducing capacity of essential oils has yet to be explored beyond clinical aromatherapy case studies. Clinical aromatherapy has the potential to diminish ...

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    Aromatherapy. Aromatherapy is the use of essential oils from plants (flowers, herbs, or trees) as a complementary health approach. The essential oils are most often used by inhaling them or by applying a diluted form to the skin. Many essential oils are used in aromatherapy, including those from Roman chamomile, geranium, lavender, tea tree ...

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    PTSD can be a difficult and impactful challenge, changing how we manage daily stress. ... Essential oils: 8 drops Sweet Orange Oil ... Achieve your aromatherapy certification with a unique case study experience! Gain a greater understanding of essential oils, and learn how to work successfully and comfortably with any client - no matter the ...

  17. Clinical Aromatherapy

    Clinical aromatherapy. Aromatherapy is a fast-growing complementary therapy worldwide. According to the National Institutes of Health National Center for Complementary and Integrative Health, Americans spend more than $30.2 billion annually on this therapy. 1 It is predicted the global market will grow in spending to $5 trillion by 2050. 2 Aromatherapy also is called integrative medicine. 3 It ...

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  20. Case Study: Aromatherapy in Long-Term Care

    Case Study: Aromatherapy in Long-Term Care. I journeyed into the mainstream healthcare system in 2013. At the time utilizing aromatherapy as a non-pharmacological option in senior care was rare. However, evidence was emerging to support its efficacy and I happened upon an opportunity to put my essential oils to the test.

  21. Case Studies PTSD and Post-Traumatic Stress Disorder

    Case Study PTSD #2: Car Accident. Ella is in her thirties, ambitious and active in life. On a wintry evening, while driving back home from work, she lost control of her car while negotiating a bend in the road. The car spun and came to a halt after it crashed into a tree. She was taken to the hospital, unconscious, with fractured ribs, a torn ...