Topical valproic acid increases the hair count in male patients with androgenetic alopecia: a randomized, comparative, clinical feasibility study using phototrichogram analysis.

Valproic acid (VPA), a widely used anticonvulsant, inhibits glycogen synthase kinase 3β and activates the Wnt/β-catenin pathway, which is associated with hair growth cycle and anagen induction. To assess the efficacy of topical VPA for treating androgenetic alopecia (AGA), we performed a randomized, double-blind, placebo-controlled clinical trial. Male patients with moderate AGA underwent treatment with either VPA (sodium valproate, 8.3%) or placebo spray for 24 weeks. The primary end-point for efficacy was the change in hair count during treatment, which was assessed by phototrichogram analysis. Of the 40 patients enrolled in the study, 27 (n = 15, VPA group; n = 12, placebo group) completed the entire protocol with good compliance. No statistical differences in age, hair loss duration and total hair count at baseline were found between the groups. The mean change in total hair count was significantly higher in the VPA group than in the placebo group (P = 0.047). Both groups experienced mostly mild and self-limited adverse events, but their differences in prevalence rates were similar between the two groups (P = 0.72). A subject treated with topical VPA developed ventricular tachycardia, but it did not seem to be related to the VPA spray. Topical VPA increased the total hair counts of our patients; therefore, it is a potential treatment option for AGA.