A randomized double-blind placebo-controlled pilot study to assess the efficacy of a 24-week topical treatment by latanoprost 0.1% on hair growth and pigmentation in healthy volunteers with androgenetic alopecia

Background: Latanoprost is a prostaglandin analogue used to treat glaucoma. It can cause adverse effects, such as iridial and periocular hyperpigmentation, and eyelash changes including pigmentation and increased thickness, length, and number. Latanoprost has been used to treat eyelash alopecia, but knowledge on its effects on human scalp hair growth is not available. Objective: The primary objectives were to assess the efficacy of latanoprost on hair growth and pigmentation. The secondary objectives were to assess the effect on scalp pigmentation; investigate the treatment duration needed to affect hair growth, hair pigmentation, and scalp pigmentation; and assess safety of latanoprost. Methods: Sixteen men with mild androgenetic alopecia (Hamilton II-III) were included. Latanoprost 0.1% and placebo were applied daily for 24 weeks on two minizones on the scalp. Measurements on hair growth, density, diameter, pigmentation, and anagen/telogen ratio were performed throughout the study. Results: At 24 weeks, an increased hair density on the latanoprost-treated site was observed compared with baseline (n = 16, P < .001) and placebo-treated site (P = .0004). Limitations: Only young men with mild androgenetic alopecia were included. The results may not be applicable to other patient groups. Choice of investigational site may have affected the results. Conclusions: Latanoprost significantly increased hair density (terminal and vellus hairs) at 24 weeks compared with baseline and the placebo-treated area. Latanoprost could be useful in stimulating hair follicle activity and treating hair loss. (J Am Acad Dermatol 2012;66:794-800.)