Description
Aromatherapy, also called essential or volatile oil therapy, entails the controlled use of essential oils that have been extracted from a variety of plant sources. Therapy is usually given via massage, inhalation or a foot- or full-body bath.
Claims of benefits for cancer patients include reduced anxiety levels and relief of emotional stress, pain, muscular tension and fatigue. Claims for the effect of certain oils range from ‘restoring harmony to the energy’ of the body, altering mood and improving overall health, to more specific claims such as having anticonvulsive and spasmolytic properties.
Efficacy
The overall evidence for aromatherapy based on three systematic reviews (including one Cochrane review) and three subsequently published randomised clinical trials provides limited evidence that aromatherapy might have positive short-term effects on quality of life, physical and psychological problems for people with cancer. There were large variations in the type of aromatherapy used, controls and outcomes in the assessed studies. Most studies had methodological limitations. The overall findings are:
Anxiety: There is evidence of possibly beneficial but small effects of aromatherapy massage but currently insufficient evidence of consistent effects of inhalation aromatherapy on reducing anxiety (2 SRs and 3 RCTs).
Depression, mood and psychological symptoms: There is currently no evidence of significant effects of aromatherapy on mood or depression in cancer patients (2 SRs and 2 RCTs).
Fatigue: There is not convincing evidence of an effect on fatigue (2 SRs).
General symptom relief: Beneficial effects are reported for aromatherapy massage on a range of self-reported physical and psychological symptoms (n=3) along with improvements in quality of life and wellbeing but the effects were not always clinically significant and risk of bias is high.
Nausea and vomiting: Only single small trials have reported positive results and further confirmation of these is required (1 SR).
Pain: Some evidence of benefit exists of aromatherapy-massage over no treatment on medium and long-term pain but effects were small. There is insufficient evidence on adding aromatherapy to massage over massage alone (3 SRs).
Phlebitis : A single small trial reported effects but further confirmation is needed.
Physiological measures: Mixed results are reported for effects on physiological measures including immune measurement (n=2), cortisol and prolactin (n=1) and vital signs (n=2).
Quality of life: Some evidence exists of a benefit of aromatherapy-massage compared with no massage but this depends on how quality of life is measured. There is insufficient evidence on adding aromatherapy to massage versus massage alone (2 SRs).
Sleep: There is some preliminary evidence of effects on sleep but this is not yet conclusive (1 SR).
Wellbeing: There is some preliminary evidence of improved wellbeing but further confirmation is needed (1SR).
Other outcomes: Gastro-intestinal related: preliminary evidence is reported for a range of outcomes including constipation (n=1), mucositis (n=2), salivary gland damage (n=1) and nutritional status (n=2). Further confirmation is needed.
Safety
Although essential oils have generally shown minimal adverse effects, when used in appropriate dilutions, allergic reactions can occur with all oils. Repeated topical administration of lavender and tea tree oil has been associated with reversible prepubertal gynecomastia, consequently there may be issues for cancer patients with oestrogen-dependant tumours.
Description and definition
Aromatherapy encompasses the controlled use of aromatic essential oils derived from many different types of plants (more often the uncrushed whole plant) claimed to possess therapeutic properties within a variety of application methods. Aromatherapy is also referred to as essential or volatile oil therapy or, more rarely, aromatic medicine.
Approximately 40 different essential oils extracted from various plants are used in aromatherapy, processed either through distillation or cold pressing (expression). Lavender, rosemary, eucalyptus, chamomile, marjoram, jasmine, peppermint, lemon, ylang ylang and geranium are some of the most popular plants used (Tisserand 1995; CRUK 2021).
Background and prevalence
Aromatic, perfumed oils were used in ancient Egypt to embalm mummies, as well as in ancient China and India. The Persian philosopher and scientist Avicenna (c. AD 980–1037) was the first to distil oil from the rose plant (Tisserand 1988). The term ‘aromatherapy’ was coined by French chemist and perfumiér René Maurice Gattefossé in his 1937 book “Aromathérapie: Les Huiles essentielles hormones végétales” as a subcategory of ‘herbal medicine’.
Gattefossé suggested aromatherapy could be used to treat diseases in virtually every organ system, citing mostly anecdotal and case-based evidence (Gattefossé 1993). Other notable aromatherapists who helped lay the foundation for modern practice are Dr Jean Valnet, who used aromatherapy to treat soldiers during WWII; Madame Marguerite Maury, an Austrian biochemist who brought aromatherapy into the world of cosmetics and developed their use in massage; and Robert B. Tisserand, an English Aromatherapist recognized for bringing aromatherapy to English speaking populations (Gattefossé 1993). In the 1980s aromatherapy increased in popularity in the USA.
Today aromatherapy is fairly well-established in countries such as Australia, Canada, France, Germany, New Zealand, Switzerland and the UK (Boehm 2012). Professional aromatherapists, nurses, physical therapists, pharmacists and massage therapists can all provide topical or inhalation aromatherapy treatment. (Wilkinson 2008) Aromatherapy use by cancer patients varies from country to country. A systematic review in 2011 showed, for example: 1% in Australia (three surveys); between <1 and 4% in Canada (two surveys); <1–2% in Italy, Spain and Turkey; 40.6% in the UK (six surveys); 11% in the USA, and 6% in New Zealand (Horneber 2012).
Alleged indications
Essential oils are used to improve physical, spiritual and emotional wellbeing. A wide range of claims have been made for the effect of certain oils, ranging from affecting the ‘subtle body’ of a patient to having anticonvulsive and spasmolytic properties. It has been suggested that the topical application of aromatic oils may exert antibacterial, anti-inflammatory and analgesic effects (NMD 2021).
It has been claimed that the application of aromatherapy can help patients with stress, chronic pain, nausea and depression; in addition they may contribute towards the relief of bacterial infections, stimulation of the immune system; it has also been asserted that they can assist in combating colds and sore throats, increasing urine production and circulation, relieving cystitis, herpes simplex, acne, headaches, indigestion, premenstrual syndrome and muscle tension. Specific indications vary according to the oils used (Hudson 1996).
For cancer patients, claims of benefits include reduced anxiety levels and relief from emotional stress, pain, muscular tension and fatigue (NMD 2021).
Mechanisms of action
The chemical properties and composition of a specific type of essential oil determines the therapeutic qualities it might have. A number of theories, which fall within the two broad categories of psychological aspects or neuro-chemical effects, try to explain the mechanisms of action. It has been suggested that effects on the limbic and olfactory system also affect mood (Boehm 2012), but only very limited research confirms such mechanisms. Proponents of essential oils/aromatherapy also believe that the overall effects these oils have on the body are greater than the sum of the individual components of the scents (Perry 2006),
Application and provider
Aromatherapy/essential oils can either be self-administered or administered by a practitioner. An aromatherapy massage typically lasts between 60 and 90 minutes. Many aromatherapists are primarily trained as massage therapists and use essential oils as part of their practice. Most commonly diluted oils are applied topically, often together with a carrier oil, as part of massage therapy to manipulate soft body tissue, or else by inhalation of the aroma using an incense burner or via ‘aromasticks’. In addition, some essential oils are ingested as teas, added to bathwater or pillows, or added to ointments, creams and compresses. It has been suggested that a safe and effective maximum dilution for most aromatherapy/essential oils in massage therapy is 2.5% for adults (2 drops of essential oil per 100 drops of carrier oil) and 5–10 drops for full-body baths.
Legal issues
There is no single regulatory organisation specifically for aromatherapy, but membership of a number of professional organisations is open to aromatherapists such as the International Federation of Aromatherapists. Also, legal restrictions apply in some countries because of the way in which essential oils can be administered, namely both orally and rectally; in such instances the application must be carried out by a medically qualified person.
Description of included systematic reviews and clinical trials
The latest Cochrane review (Shin 2016) evaluated massage with or without aromatherapy for symptom relief in people with cancer. This systematic review (SR) presented evidence from six randomized controlled trials (RCTs) comparing aromatherapy massage with no massage and two RCTs comparing aromatherapy massage and massage without aromatherapy. The review concludes that there is limited evidence that aromatherapy may be useful for people with cancer in terms of relief from pain and anxiety, this was due to methodological limitations of studies. Two further systematic reviews (n=43, n=3) plus several RCTs have been published subsequently.
Anxiety
A Cochrane review in 2016 on symptom relief for cancer patients offered by massage with or without aromatherapy included five RCTs that assessed effects on anxiety (Shin 2016). Four compared massage with aromatherapy versus no-massage, one trial also compared massage plus aromatherapy with massage alone and one only compared aromatherapy massage with massage alone. The quality of the evidence was judged very low due to high risk of bias. While there was some evidence of benefit of aromatherapy-massage over no treatment on anxiety (two RCTs, n=253, combined MD -4.50, 95% CI -7.70 to -1.30), the effects were small and not considered clinically significant. Insufficient evidence was found on the potential benefit of adding aromatherapy to massage over massage alone.
A subsequent systematic review published in 2019 included 16 studies that assessed effects of aromatherapy on anxiety, the majority involving aromatherapy in combination with massage and the use of lavender oil. (Farahani 2019) The authors concluded that aromatherapy relieved ‘a various range of cancer related symptoms including: Anxiety…’.Six of these studies were not randomised studies and four of the RCTs were included in the Cochrane review above. Of the six RCTs not included in the Cochrane review, four were on the use of aromatherapy for anxiety related to various procedures. Aromatherapy massage with lavender oil prior to colorectal surgery was more effective than no treatment in one trial. Mixed result were reported for inhalation of various essential oils during chemotherapy, radiotherapy and infusion of stem cells. Two RCTs in breast cancer patients, one using aromatherapy inhalation and one using aromatherapy massage reported beneficial effects. All RCTs were rated at least 3 out of 5 on the Jadad scale but blinding is not possible and the outcome is subjective and self-assessed and thus prone to bias.
Three further RCTs, not included in either of the reviews above, include a feasibility study of aromatherapy massage versus cognitive behavioural therapy which found non-significant differences (Serfaty 2012); a trial of Citrus aurantium (orange oil) versus diazepam and saline in which groups were not matched at baseline (Pimenta 2016) and a trial in which non-significant differences were found between acupressure with essential oils and acupressure alone. (Tang 2014)
Thus, it appears that the conclusions of the Cochrane review still apply: possibly beneficial but small effects of aromatherapy massage. There is currently insufficient evidence of consistent effects of inhalation aromatherapy on reducing anxiety.
Depression, mood and psychological symptoms
The Cochrane review included four RCTs comparing aromatherapy massage to no treatment (Shin 2016). Three of these were small (n=32-66) and one larger (n=221) trial used different outcomes measures but no significant difference was seen in each case. One trial assessed effects on mood disturbances and one assessed psychological symptoms but both were small and, again, no significance differences were measured. No difference was seen between aromatherapy massage and massage alone on psychological symptoms. One trial of aromatherapy massage versus massage alone did report significant reductions in depression scores in the massage group but the trial was small data was not evaluable.
A more recent SR stated that six of the included studies investigated the effect of aromatherapy massage (n=5) and inhalation aromatherapy (n=1) on depression (Farahani 2019). The review states that inhalation aromatherapy does not have a significant effect and aromatherapy massage reduced depression in cancer patients in all studies. The table of studies, however, indicates that depression had been measured in 11 studies and it is unclear why only six studies are summarised. Lavender was the most commonly used aroma.
Two further RCTs have been published: one found improvements with aromatherapy massage and cognitive behavioural therapy (CBT) but no significant difference between these. (Serfaty 2012) The trial was, however, a pilot study and may have not been sufficiently large to detect a difference. The other trial of acupressure with essential oils, acupressure only and sham acupressure suffered similar problems (Tang 2014).
Thus, there is currently no evidence of significant effects of aromatherapy on mood or depression in cancer patients.
Fatigue
The Cochrane review reported on two trials that assessed effects on fatigue (Shin 2016). A large RCT (N=221) found no significant difference between aromatherapy‐massage using a range of essential oils and usual care only (no massage). While the second, smaller study did report a difference, appropriate data was not available for meta-analysis.
A subsequent SR included four studies on fatigue all reporting positive effects of aromatherapy (Farahani 2019). One of these trials was included in the Cochrane review and one was not an RCT. The two remaining RCTs, one recent (n=46) and one older study (n=87), both involved use of chamomile and both reported improved fatigue with aromatherapy massage compared with usual care or massage alone.
One further RCT found no significant difference between acupressure with essential oils and acupressure alone (Tang 2014).
Overall, there is not convincing evidence of an effect on fatigue.
Nausea and vomiting
No studies assessing the effects of aromatherapy in nausea and vomiting were included in the Cochrane review (Shin 2016).
Nine studies including seven RCTs were included in a subsequent systematic review (Farahani 2019). Two studies (n=66, 87) reported positive effects of aromatherapy massage using ginger/coconut and chamomile respectively on nausea along with various other outcomes. The remaining five RCTs employed inhalation: two trials of ginger and one of bergamot reported no effect. One trial (n=66) reported positive effects of cardamom on nausea and a trial (n=100) of peppermint oil reported significant but small effects.
The wide range of different oils that have been used mean that it is currently unclear if there is a beneficial effect from some oils and not others. Only single small trials have reported positive results and further confirmation of these is required.
Pain
The Cochrane review in 2016 on symptom relief for cancer patients offered by massage with or without aromatherapy included five RCTs that assessed effects on pain (Shin 2016). All five compared massage with aromatherapy versus no-massage and one trial also compared massage plus aromatherapy with massage alone. The quality of the evidence was judged very low due to high risk of bias. While there was some evidence of benefit of aromatherapy-massage over no treatment on medium and long-term pain (medium-term: one RCT, n = 86, MD 5.30, 95% CI 1.52 to 9.08; long-term: one RCT, n = 86, MD 3.80, 95% CI 0.19 to 7.41), the effects were small and not considered clinically significant. Insufficient evidence was found on the potential benefit of adding aromatherapy to massage over massage alone.
Chen et al. (2016) conducted a meta-analysis of RCTs to look at the clinical effectiveness of aromatherapy massage on reducing pain. The authors identified three studies meeting their criteria for inclusion in the meta-analysis, only one of these studies was also included in the above Cochrane review by Shin et al. Chen et al.’s meta-analysis pooled data from 278 participants (135 in aromatherapy and 143 participants in control group). Aromatherapy had a non-significant effect on reducing pain (standardized mean difference, SMD=0.01; 95% CI −0.23, 0.24).
A systematic review published in 2019 included a total of 13 studies on pain: 3 of those included in the Cochrane review plus 10 additional studies (Farahani 2019). Six of the additional studies were not randomised trials. The four additional RCTs included a study of essential oils used in a gargle for oral mucositis and related pain and one using an essential oil mixture applied to the skin for radiation-related skin reactions. A third involved inhalation aromatherapy prior to sickle cell infusion therapy and the fourth was a trial published in Chinese that involved an aromatherapy and music intervention. The review concluded that aromatherapy relieved pain but few details were presented in support of this other than that the majority of studies reported beneficial effects (3 found no effect).
Quality of life
In assessing the effect of adding aromatherapy to massage against that of massage alone, the Cochrane review concluded that the quality of evidence was very low with studies at a high risk of bias (Shin 2016). There was some indication of benefit of aromatherapy-massage in that the medium-term (4-8 weeks) quality of life score was lower (better) than in a no-massage group (one RCT, n = 30, MD -2.00, 95% CI -3.46 to -0.54). Two trials using difference outcome measures found no difference. There was insufficient evidence on adding aromatherapy to massage versus massage alone.
A subsequent systematic review included nine studies on quality of life, three of which were included in the Cochrane review (Farahani 2019). Three RCTs tested aromatherapy-massage, two tested inhalation aromatherapy and one tested both forms. Inhalation aromatherapy was not effective in one study and less effective than aromatherapy massage in another trial. Three of the four RCTs found aromatherapy massage to be effective.
Overall, the evidence for aromatherapy massage was more convincing than for inhalation aromatherapy. Quality of life is, however, a self-assessed subjective measure and patients could not be blinded to treatment.
Sleep
The Cochrane review did not report any results on sleep (Shin 2016).
Four studies on sleep were included in the more recent SR, involving between 45 and 80 participants: three tested inhalation of various essential oils and one compared massage with lavender oil with usual care (Farahani 2019). All 4 reported positive findings and were rated as good quality in the review (Jadad score of at least 3) but blinding was not possible and sleep quality was self-rated and, therefore, prone to bias.
One further RCT found some differences in sleep quality between acupressure with essential oils and acupressure alone but these were not consistent at both time points measured.37
Overall, there is some preliminary evidence of effects on sleep but this is not yet conclusive.
Wellbeing
Wellbeing was not assessed in the Cochrane review (Shin 2016).
The more recent systematic review included two studies on wellbeing, both of which showed beneficial effects of aromatherapy massage (Farahani 2019).
Other outcomes
Symptoms relating to the breast
The relief of long-term symptoms relating to the breast in people with breast cancer (one RCT, n = 86, MD -9.80, 95% CI -19.13 to -0.47) was greater for the aromatherapy-massage group than no treatment, but the results were considered not clinically significant (Shin 2016). There was insufficient evidence to assess the effect of adding aromatherapy to massage on physical symptom distress.
A wide range of other outcomes have been assessed and the studies were summarised in the most recent systematic review (Farahani 2019). The following is a list of the outcomes for which there is preliminary evidence based on one or two (generally small) trials:
Gastro-intestinal related
Constipation (n=1), positive results were reported in a small trial (n=32) for aromatherapy-massage compared with massage alone.
Oral mucositis (n=2), two RCTs each using a mouthwash/gargle containing essential oils (Matricaria recutita and Mentha piperita, n=60; manuka and kanuka oils, n=19). Positive results were reported in both trials.
Salivary gland damage (n=1), positive results were reported with use of inhaled aromatherapy in one trial (n=71).
Nutrition status (n=2), using a gargle and using inhaled aromatherapy (ginger oil; Manuka, kanuka oils), in two trials (n=19; 60), both of which were reported positive effects.
Chemotherapy-Induced phlebitis (n=1)
Using aromatherapy massage with sesame oil was reported to be more effective than massage alone in prevention of phlebitis (n=60).
Physical and psychological symptom relief (n=3)
using aromatherapy massage and inhalation: RCTs have shown beneficial effects on a range of self-reported physical and psychological symptoms along with improvements in quality of life and wellbeing.
Physiological measures
The evidence for effects on physiological measures is mixed:
- Immune measurements (n=2), aromatherapy massage: mixed results are reported for effects on the immune system, one trial (n=66) reporting an effect and the other (n=12), no effect although this may be due to the trial being underpowered.
- Cortisol and prolactin (n=1) aromatherapy massage: positive effects were reported (alongside improved quality of life) in one small RCT (n=39).
- Vital signs (n=2): a large RCT (n=153) found no effect of inhalation aromatherapy while two small RCTs (n=20; 42) reported an improvement in the vital signs. One RCT assessed effects on blood pressure, cardiac and respiratory frequency as part of an assessment of effects on anxiety.
Aromatherapy is considered safe when administered by a qualified aromatherapist whose expertise includes working with the needs of people who have cancer.
Aromatherapy oil
Tests of essential oils for safety have shown minimal adverse effects. A number of oils have therefore been approved for use as food additives and are classified as GRAS (generally recognised as safe) by the US Food and Drug Administration. Nevertheless there is a risk involved in the consumption of essential oils (FDA 2020). Also, a review on the safety assessment of St John’s wort (Hypericum perforatum) oil has concluded that the available data are insufficient to support the use of ingredients from this plant as safe for use in cosmetic formulations (Anon 2001).
Adverse events
Some essential oils (e.g. camphor oil) can cause local irritation. The main concern with essential oils seems to be regarding cases of contact dermatitis, mostly reported in aromatherapists who have had prolonged skin contact with oils in the context of aromatherapy massage. Moreover, phototoxicity has been found to occur when essential oils (particularly citrus oils) are applied directly to the skin before exposure to the sun (Clark 1998).
Odours from essential oils may result in adverse psychological responses, especially if the memory of a particular scent evokes strong emotions (Holmes) In addition, Hongratanaworakit et al. have reported that sweet orange oil (Citrus sinensis) can have a stimulatory effect on the cardiovascular system (Hongratanaworakit 2005).
Contraindications
One study has shown that repeated topical exposure to lavender and tea tree oils by topical administration was associated with reversible prepubertal gynecomastia (Henley 2007). Therefore, these two essential oils could cause problems in patients with oestrogen-dependant tumours.
Further contraindications, especially for people with cancer, are associated with contagious diseases, broken skin, varicose veins and circulatory disorders (Ernst 2008). Caution is also indicated for those who are pregnant, or trying to get pregnant, breastfeeding, or have kidney disease, liver disease, asthma or epilepsy (AIA 2021).
Interactions
Drugs that act as depressants on the central nervous system can interact adversely with aromatherapy. These drugs include narcotics such as morphine or oxycodone (OxyContin) for pain, as well as sedative and anti-anxiety agents such as lorazepam (Ativan), diazepam (Valium) and alprazolam (Xanax) (drugs.com 2021). Some aromatherapies can cause sleepiness or drowsiness.
Warnings
Aromatherapy inhalation should not be used by people with asthma.
Alliance of International Aromatherapists. A brief history of aromatherapists. Accessed 15th November 2019.
Anonymous. Final report on the safety assessment of Hypericum perforatum extract and Hypericum perforatum oil. International Journal of Toxicology. 2001;20 Suppl 2:31-9.
Boehm K, Büssing A, Ostermann T. Aromatherapy as an adjuvant treatment in cancer care--a descriptive systematic review. Afr J Tradit Complement Altern Med 2012;9:503-18. eCollection 2012. Review.
Cancer Research UK. Aromatherapy, [website], accessed 15th November 2019.
Chen TH, Tung TH, Chen PS, Wang SH, Chao CM, Hsiung NH, et al. The Clinical Effects of Aromatherapy Massage on Reducing Pain for the Cancer Patients: Meta-Analysis of Randomized Controlled Trials. Evidence-based complementary and alternative medicine : eCAM. 2016;2016:9147974.
Clark SM, Wilkinson SM. Phototoxic contact dermatitis from 5-methoxypsoralen in aromatherapy oil. Contact Dermatitis 1998;38: 289–90.
Drugs.com. Treatment Options Herbal Supplementation: Lavender. Available online, accessed 15th November 2019.
Ernst E, Pittler MH, Wider B, Boddy K. The Oxford Handbook of Complementary Medicine. Oxford: Oxford University Press, 2008.
Farahani MA, Afsargharehbagh R, Marandi F, Moradi M, Hashemi SM, Moghadam MP, Balouchi A. Effect of aromatherapy on cancer complications: A systematic review. Complement Ther Med. 2019;47:102169.
FDA, US Food and Drug Administration. CFR - Code of Federal Regulations Title 21. April 1st 2020.
Gattefossé RM. Gattefossé's Aromatherapy. Edited by R Tisserand, Translated by L Davies. Saffron Waldon: The CW Daniel Company, 1993.
Henley DV, Lipson N, Korach KS, et al. Prepubertal gynecomastia linked to lavender and tea tree oils. N Engl J Med 2007; 356:479-85.
Holmes C, Ballard C. Aromatherapy in dementia. Advances in Psychiatric Treatment 2004; 10: 296–300.
Hongratanaworakit T, Buchbauer G. Human behavioral and physiological reactions to inhalation of sweet orange oil. Acta Hort 2005;679:75-81.
Horneber M, Bueschel G, Dennert G, Less D, Ritter E, Zwahlen M. How many cancer patients use complementary and alternative medicine: a systematic review and metaanalysis. Integr Cancer Ther 2012;11:187-203.
Hudson R. The value of lavender for the rest and activity in the elderly patient. Complement Ther Med. 1996;4:52–7.
NMD, Natural Medicines Database. Aromatherapy [web resource, requires subscription], accessed 15th November 2019.
Perry N, Perry E. Aromatherapy in the management of psychiatric disorders: clinical and neuropharmacological perspectives. CNS Drugs 2006;20: 257-80.
Pimenta F, Alves M, Pimenta M, Melo S, Almeida A, Leite J, et al. Anxiolytic effect of Citrus aurantium L. on patients with chronic myeloid leukemia. Phytother Res 2016;30:613-7.
Serfaty M, Wilkinson S, Freeman C, Mannix K, King M. The ToT Study: Helping with Touch or Talk (ToT): a pilot randomised controlled trial to examine the clinical effectiveness of aromatherapy massage versus cognitive behaviour therapy for emotional distress in patients in cancer/palliative care. Psychooncology 2012;21:563-9.
Shin ES, Seo KH, Lee SH, Jang JE, Jung YM, Kim MJ, et al. Massage with or without aromatherapy for symptom relief in people with cancer. The Cochrane database of systematic reviews. 2016(6):Cd009873.
Tang WR, Chen WJ, Yu CT, Chang YC, Chen CM, Wang CH, Yang SH. Effects of acupressure on fatigue of lung cancer patients undergoing chemotherapy: an experimental pilot study. Complement Ther Med 2014;22:581-91.
Tisserand R, Balacs T. Essential oil safety. Edinburgh: Churchill Livingstone, 1995.
Tisserand R. Essential oils as psychotherapeutic agents. In: Van Toller S, Dodd GH, eds. Perfumery: The Psychology and Biology of Fragrance. New York, NY: Chapman and Hall, 1988, pp 167-80.
Wilkinson S, Barnes K, Storey L. Massage for symptom relief in patients with cancer: systematic review. J Adv Nurs 2008;63:430-9.
Citation
Pilkington K, Seers H, CAM Cancer Collaboration. Aromatherapy [online document]. Feb 14, 2020.
Document history
Summary fully revised and updated in December 2019 by Karen Pilkington.
Summary fully revised and updated in May 2017 by Helen Seers.
Summary fully revised and updated in December 2015 by Helen Seers.
Last updated in September 2013 by Katja Boehm.
Summary fully revised and updated in June 2012 by Katja Boehm.
Summary first published in March 2011, authored by Katja Boehm and Thomas Ostermann.
