Eighty-four patients with endoscopically-proved active duodenal ulcer were admitted to a multicentre double-blind trial with either pirenzepine tablets (25 mg three times per day for 1 week followed by 25 mg two times per day for 3 weeks) or placebo. Seventy-nine patients completed the trial, 44 treated with pirenzepine and 35 with placebo. After 4 weeks, complete healing had been achieved in 52% of the pirenzepine-treated patients and in 34% of the placebo-treated ones. Symptomatic responses were signigicantly better in those receiving pirenzepine than in those receiving placebo. In addition, the supplementary antacid consumption was significantly lesser in the pirenzepine group than in the placebo group. No important side-effects were observed in the two groups.