Comparison of the efficacy of tea tree (Melaleuca alternifolia) oil with other current pharmacological management in human demodicosis: A Systematic Review

• Published in: Parasitology Vol. 147; no. 14; pp. 1587 - 1613
• Main Authors: Lam, Nelson Siu Kei, Long, Xin Xin, Li, Xuegang, Yang, Li, Griffin, Robert C, Doery, James CG
• Format: Journal Article
• Language: English
• Published: Cambridge, UK Cambridge University Press 01.12.2020
• Subjects: Acaricides - therapeutic use; Acne; Alopecia; Antigens; Antiinfectives and antibacterials; Antiparasitic agents; Baldness; Biofilms; Demodex; Dermatitis; Drug delivery; Drug delivery systems; Essential oils; Fungi; Fungicides; Humans; Immune system; Infections; Inflammation; Insecticides; Ivermectin; Melaleuca alternifolia; Metronidazole; Mite Infestations - drug therapy; Mites; Pathogenesis; Permethrin; Review; Side effects; Signs and symptoms; Systematic review; Tea tree oil; Tea Tree Oil - therapeutic use; Terpinene; Toxicity; Tumor necrosis factor-TNF; Wound healing; demodicosis; tea tree oil; Crotamiton; permethrin; terpinen-4-ol; metronidazole; ivermectin; lindane
• ISSN: 0031-1820; 1469-8161
• DOI: 10.1017/S003118202000150X

Various treatments are found to be moderately effective in managing Demodex-related diseases except tea tree oil (TTO) and terpinen-4-ol (T4O), which showed superior miticidal and anti-inflammatory effects in numerous clinical studies. Their possible effects include lowering mite counts, relieving Demodex-related symptoms, and modulating the immune system. This review summarizes the current clinical topical and oral treatments in human demodicosis, their possible mechanisms of action, side-effects and resistance in treating this condition. TTO (especially T4O) is found to be the most effective followed by metronidazole, ivermectin and permethrin in managing the disease. This is because TTO has anti-parasitic, anti-bacterial, anti-fungal, anti-inflammatory and wound-healing effects. Furthermore, nanoTTO can even release its contents into fungus and Pseudomonas biofilms. Combinations of different treatments are occasionally needed for refractory cases, especially for individuals with underlying genetic predisposal or are immuno-compromised. Although the current treatments show efficacy in controlling the Demodex mite population and the related symptoms, further research needs to be focused on the efficacy and drug delivery technology in order to develop alternative treatments with better side-effects profiles, less toxicity, lower risk of resistance and are more cost-effective.