New York Presbyterian Hospital/Columbia University Medical Center Family Medicine Residency Program, New York City (Drs. Shah, Killeen, and Meninno, and Shoshana Shine); Neighborhood Health, Alexandria, VA (Dr. Killeen) pas2176@cumc.columbia.edu
The authors reported no potential conflict of interest relevant to this article.
Given the ubiquity of these plant-based oils, your patients might ask about using them. Here’s the evidence on safety and efficacy to guide your response.
› Utilize lavender essential oil as an adjunctive treatment for fibromyalgia, dysmenorrhea, anxiety, and insomnia symptoms. B
› Recommend peppermint essential oil as an adjunctive treatment for irritable bowel syndrome, chemotherapy-induced nausea, and headache. B
Strength of recommendation (SOR) A Good-quality patient-oriented evidence B Inconsistent or limited-quality patient-oriented evidence C Consensus, usual practice, opinion, disease-oriented evidence, case series
References
Essential oils (EOs), which are concentrated plant-based oils, have become ubiquitous over the past decade. Given the far reach of EOs and their longtime use in traditional, complementary, alternative, and integrative medicine, it is imperative that clinicians have some knowledge of the potential benefits, risks, and overall efficacy.
Commonly used for aromatic benefits (aromatherapy), EOs are now also incorporated into a multitude of products promoting health and wellness. EOs are sold as individual products and can be a component in consumer goods such as cosmetics, body care/hygiene/beauty products, laundry detergents, insect repellents, over-the-counter medications, and food.
It is important to read ingredient labels before purchasing an essential oil. Reputable companies will identify the plant ingredient, usually by the formal Latin binomial name, and explain the extraction process.
The review that follows presents the most current evidence available. With that said, it’s important to keep in mind some caveats that relate to this evidence. First, the studies cited tend to have a small sample size. Second, a majority of these studies were conducted in countries where there appears to be a significant culture of EO use, which could contribute to confirmation bias. Finally, in a number of the studies, there is concern for publication bias as well as a discrepancy between calculated statistical significance and actual clinical relevance.
What are essential oils?
EOs generally are made by extracting the oil from leaves, bark, flowers, seeds/fruit, rinds, and/or roots by steaming or pressing parts of a plant. It can take several pounds of plant material to produce a single bottle of EO, which usually contains ≥ 15 to 30 mL (.5 to 1 oz).1
Some commonly used EOs in the United States are lavender, peppermint, rose, clary sage, tea tree, eucalyptus, and citrus; however, there are approximately 300 EOs available.2 EOs are used most often via topical application, inhalation, or ingestion.
As with any botanical agent, EOs are complex substances often containing a multitude of chemical compounds.1 Because of the complex makeup of EOs, which often contain up to 100 volatile organic compounds, and their wide-ranging potential effects, applying the scientific method to study effectiveness poses a challenge that has limited their adoption in evidence-based practice.2
Availability and cost.EOs can be purchased at large retailers (eg, grocery stores, drug stores) and smaller health food stores, as well as on the Internet. Various EO vehicles, such as inhalers and topical creams, also can be purchased at these stores.
