RESUMO
Background: In addition to its low toxicity risk, Lavender (Lavandula angustifolia Mill.) essential oil is recognised worldwide for its sedative, antidepressant, antiseptic, antifungal, relaxing, and antiemetic properties. Thus, the action mechanism of lavender oil has attracted significant attention from researchers interested in improving the physical, emotional, and spiritual well-being of patients. Objective: To investigate the scope of knowledge regarding the use of L. angustifolia essential oil as a complementary therapy in adult health care. Methods: A scoping review was carried out using a PRISMA-ScR checklist followed by a critical assessment being performed using the Joanna Briggs Institute level of evidence. The following databases were used: SCOPUS, MEDLINE/PubMed, Web of Science, Science Direct, SCIELO, Cochrane Library, LILACS, Wiley Online Library, CAPES, and FIOCRUZ Dissertations. Results: Eighty-three articles published between 2002 and 2022 were selected for the analysis; More articles came from Iran than from any other country and most articles reported clinical trials. The applicability of lavender essential oil and its route of administration in different clinical situations were the main topics addressed in the articles. Conclusions: Most studies demonstrate the efficacy of L. angustifolia Mill. essential oil in relieving pain and decreasing anxiety. Few studies evaluated the anti-psoriatic, anti-toxoplasmotic, and wound healing properties and the protective actions against cerebral ischemia. One study reported on its safety, specifically the allergenic potential of linalool, the main chemical component of L. angustifolia essential oil. However, most studies did not involve the extensive investigations on this topic or report the safe quantities of this oil for human treatment, meaning further research into the safety of this treatment is required.