Acne, a common skin disease, affects people from adolescence through adulthood. Regardless of an individual’s age, primary and secondary acne lesions can have negative psychosocial effects. Complementary and alternative medicine (CAM) may offer benefits whether used in a complementary fashion or as an alternative to conventional treatments. CAM acne treatments have not been well-studied by Western methods, especially in children and adolescents. CAM approaches to skin problems include topical botanical extracts; plant essential oils (EOs) and aromatherapy; “herbal therapy”; and acupuncture. The author focuses on use of EOs for acne management.
An opening section, “Clarification of relevant terms,” is rather less than clear. Winkelman writes that EOs may be mixed in gels, compounded into pastes or sprays, or applied via baths, massage, or inhalation. He defines aromatherapy as therapeutic use of EOs. However, stating that EOs “are believed to be absorbed through the upper part of the dermis” ignores the defining pathway of aromatics: the nose and its limbic connection to the brain. Given the role of stress in acne, aromatherapy using calming, anxiolytic EOs could be of interest but is not mentioned. Nor are any EOs applied via inhalation mentioned in this article. The author discusses United States (US) Food and Drug Administration (FDA) definitions of drugs and cosmetics. Products sold as cosmetics (e.g., perfumes, shampoos) may claim to promote attractiveness through fragrance, but those marketed “with certain ‘aromatherapy’ claims, such as reducing the number of acne lesions or improving acne, meet the definition of a drug.” Massage oils claiming to relieve skin irritation are also, he says, drugs under these rules. Making a drug claim requires specific evidence and procedures under FDA rules. A later reference to “cosmeceuticals” further clouds this discussion. Under “Mechanisms of action,” neither skin nor nasal absorption is mentioned, but theories, including “systemic effects (drug or enzyme), placebo effects, or general affective or ‘reflectorial’ effects that induce positive moods” are listed. EOs rich in ketones are associated with wound-healing properties; those high in alcohols, with antimicrobial/anti-infective activities. A table of types of organic compounds in EOs and their proposed therapeutic actions is useful and might have been further discussed.
Possible alternative acne treatments include tea tree (Melaleuca alternifolia, Myrtaceae) EO (TTO). Well-characterized and with an international standard, it has been used medicinally for many years in some nations. In the US, most TTO has ~100 terpenes, with 40% terinen-4-ol. TTO is used in many over-the-counter (OTC) acne products. An evidence-based review of botanicals in dermatology concluded that TTO could become a standard acne treatment. In a clinical study, 5% TTO vs. 5% benzoyl peroxide had slower onset of effects but better tolerability. In a randomized placebo-controlled trial (RCT), patients with mild to moderate acne who used TTO 45 days had reduced total, inflammatory, and noninflammatory lesions compared to those using placebo. A Cochrane analysis, however, found the evidence for TTO of low methodological quality.
Hinoki false cypress (Chamaecyparis obtusa, Cupressaceae) steam-distilled leaf extract is widely used in cosmetics. Fermentation with Lactobacillus fermentum yields an extract, LFCO, that strongly inhibits Propionibacterium acnes. In an eight week, randomized, split-face study in 34 patients with mild to moderate acne, LFCO produced faster effects than TTO (P<0.05), greater effect on inflammation and inflammatory markers, and 65.3% reduction of inflammatory lesions compared with 38.2% for TTO-treated skin. LFCO reduced sebaceous gland size and sebum production. Authors of that study compared LFCO’s effects to retinoids and antibiotics, with fewer adverse effects (AEs). Copaiba (Copaifera spp., Fabaceae) oleoresin from tree trunks, eponymously called “copaiba,” is a traditional South and Central American medicine for wound healing. It is anti-inflammatory, antiseptic, and promotes healing. Active compounds are diterpenes. In a 21-day double-blind study, copaiba EO and placebo both reduced inflammation and lesions, but nonstandard measures made results difficult to compare with other studies.
Possible complementary acne treatments use EOs from sandalwood (Santalum album, Santalaceae), rosemary (Rosmarinus officinalis, Lamiaceae) extract, Jeju EO from thyme (Thymus quinquecostatus, Lamiaceae), found on the island of Jeju, South Korea, and EOs from kinkoji (Citrus obovoidea, Rutaceae) and amanatsu (Natsudaidai orange, Japanese summer orange; C. natsudaidai). Sandalwood EO is used in Asia for skin eruptions. It inhibits Staphylococcus aureus and P. acnes. Synthetic sandalwood induced wound healing in human keratocytes. In an eight week open-label trial, 89% of 42 patients with mild to moderate acne who used 0.5% salicylic acid with sandalwood in a 4-part cleansing regimen saw global improvement, with 37% mean decrease in inflammatory, 25% in noninflammatory, and 31% in total lesions compared to baseline. Products were mostly well-tolerated. Three rosemary compounds modulate cytokine production via different mechanisms. While rosemary extract in “cosmeceutical” or dermatologic products may boost their anti-inflammatory effects, its “injection… is not associated with… irritation or inflammation in the mouse model.” Jeju oil may be active against P. acnes. The other two EOs are characterized as “Korean citrus” despite the apparent Japanese origin of at least one. Tested against P. acnes and S. epidermidis, they reduced P. acnes secretions of interleukin-8 and tumor necrosis factor α.
No studies have reported on psychosocial outcomes of botanical acne treatments, cost effectiveness or other advantages, or possible effects on hyperpigmentation. Clinical evidence is sketchy to nonexistent. Nonetheless, dermatologists should be familiar with CAM options in order to respond to patient interest.
Winkelman WJ. Aromatherapy, botanicals, and essential oils in acne. Clin Dermatol. May-June 2018;36(3):299-305. doi: 10.1016/j.clindermatol.2018.03.004.