Risk of valproic acid-related alopecia: A systematic review and meta-analysis.

PURPOSE: We systematically reviewed studies to provide current evidence about the incidence and risk of alopecia in patients undergoing valproic acid (VPA) therapy. METHODS: We retrieved relevant publications and gathered data on alopecia in patients taking VPA and other drugs from prospective studies. RESULTS: Twenty-five articles met the inclusion criteria, and the overall incidence of alopecia in patients receiving VPA therapy was 11% (95% confidence interval (CI): 0.08-0.13). The pooled risk of alopecia showed a significant difference between patients treated with VPA and all other drugs (odds ratio (OR) 5.02, 95% CI: 3.58-7.03), other epileptic drugs (AEDs) (OR 4.82, 95% CI: 3.32-7.00) and other non-AEDs (OR 5.84, 95% CI: 2.67-12.81). Compared to other drugs, VPA increased the risk of alopecia both in patients with migraine headaches (OR 6.05, 95% CI: 2.89-12.63) and patients with epilepsy (OR 5.29, 95% CI: 3.53-7.92), and the increase risk was reported more frequently in patients with migraine. Both lower doses (OR 4.38, 95% CI: 2.32-8.25) and shorter treatments (OR 4.98, 95% CI: 2.41-10.25) with VPA posed a high risk of alopecia compared to other drugs, as did higher doses and longer treatment times. CONCLUSIONS: Based on our findings, VPA was significantly associated with a risk of alopecia compared to other drugs, and the risk did not depend on the dose and treatment time.