Failure of papaverine to reduce pruritus in atopic dermatitis: a double-blind, placebo-controlled cross-over study.

Papaverine has been reported, largely on the basis of clinical experience, to reduce the severity of pruritus associated with atopic dermatitis. A double-blind, placebo-controlled, cross-over study was performed to assess the degree of improvement. Fifty subjects with atopic dermatitis each received papaverine 100 mg q.d.s. orally for 4 weeks and another 4 weeks of matching placebo in randomized order. The parameters used to measure response were pruritus as assessed on visual analogue scales by the subjects, clinical scoring of extent and severity of the dermatitis and rate of usage of topical steroid preparations. Forty-five subjects completed the protocol and no improvement in any parameter was demonstrated.