ABSTRACT
Pirenzepine is an antimuscarinic drug highly selective for M1 receptors, which proved to be effective in the treatment of peptic ulcer. Aim fo the present study was to assess the frequency of relapses over a 12-month period subsequent to the anatomic healing of duodenal ulcer, obtained with pirenzepine (PRZ). Sixty patients (44 M, 16 F, mean age 42,9 years range 19-73) entered the study. They were allocated at random to a double-blind treatment with placebo or PRZ given at two different dosages, 50 or 100 mg/day respectively, over a consecutive period of 12 months. Clinical evaluations were foreseen every 3 months, while endoscopy and hematology, gastrin plasma levels and intra-ocular pressure assessment at the end of the 6th and 12th month. The intake of antacids or equivalent drugs, in addition to the baseline treatment, was not allowed. Statistical evaluation of the results was performed by chi-square test with Yates' corrections. Difference in percentage of patients without relapses at 6th month and at 12th month was clearly in favour of PRZ compared with placebo. Non changes in the indices of gastrin plasma levels, liver or renal functions and intraocular pressure were reported. No patients complained of side-effects pirenzepine-related. The treatment with full dosage (100 mg/day) did not increase the rate of positive responsiveness compared to that of standard dosage (50 mg/day). It might confirm the importance of the role played by nocturnal acid secretion. For this reason, a decrease in relapses could be expected with the dosage of 100 mg if it was given in a single evening dose. However, therapy with PRZ turned out effective and did not produce side-effects. Its selectivity avoided clinical effects related to a cholinergic system block.
