Double-blind study of a new antimuscarinic, cimetropium bromide, in patients with irritable bowel syndrome.

Forty patients with irritable bowel syndrome were randomly allocated to treatment with octylonium bromide (20 mg TID) or cimetropium bromide (50 mg BID) in a double-blind trial lasting for six weeks. Drugs were taken before meals, according to a double-blind schedule. Clinical evaluations were made of digestive and other symptoms, objective findings (pain at palpation, contracted colon, tympanites), and overall effectiveness of treatment. Statistically significant decreases in severity of abdominal pain and subjective scores for bowel habits were obtained in both groups. The only statistically significant differences between treatments were in nondigestive symptoms (asthenia, palpitations, tremor, headache, etc.), which improved more in the cimetropium bromide group. No severe side effects were observed in either treatment group.