Melatonin and the Human Hair Follicle

The paper "Melatonin and the Human Hair Follicle" reviews the scientific evidence supporting the potential benefits of melatonin in human hair growth. The authors conducted a literature review using three databases and identified 11 human studies involving 2,267 patients with diagnosed alopecia. Eight of these studies observed positive outcomes after topical melatonin use in subjects with androgenetic alopecia (AGA). Most studies reported improved scalp hair growth (8 studies), density (4 studies), and hair shaft thickness (2 studies) among melatonin users compared to controls. The effective topical melatonin dosage appears to be 0.0033% or 0.1% solution applied once-daily for 90 to 180 days, or 1.5 mg twice-daily oral melatonin supplementation for 180 days. The authors conclude that there is evidence to support melatonin use to facilitate scalp hair growth, particularly in men with AGA, but further studies are needed to investigate the mechanism of action.