Efficacy and safety of diphenylcyclopropenone alone or in combination with anthralin in the treatment of chronic extensive alopecia areata: A retrospective case series

BackgroundSome patients with chronic extensive alopecia areata (AA) may be refractory to topical immunotherapy. Combination therapy is recommended for such patients. Efficacy and safety of a combination therapy with diphenylcyclopropenone (DPCP) and anthralin in chronic extensive AA is unknown.ObjectiveWe sought to determine whether the combination therapy of DPCP and anthralin is superior to DPCP alone in chronic extensive AA.MethodsWe retrospectively analyzed the efficacy, side effects, and relapse rates of DPCP (alone or with anthralin) in chronic extensive AA.ResultsA total of 47 patients (22 were treated only with DPCP, and 25 with DPCP and anthralin for at least 30 weeks) were evaluated. Complete hair regrowth was observed in 36.4% and 72% of the patients who received DPCP and combination therapy, respectively (P = .01). Hair regrowth duration was shorter with combination therapy (P = .01). Regrowth rates of the eyebrows, eyelashes, and beard in patients on combination therapy were higher than those in patients on DPCP (P = .01). Side effects such as folliculitis, hyperpigmentation, and staining of skin, hair, and clothes were more common in combination therapy group.LimitationsThe retrospective design and small number of patients are limitations.ConclusionCombination therapy with DPCP and anthralin is superior to DPCP alone in chronic extensive AA.