In 5 patients with diverticular disease, colonic motilities of the proximal and distal colon were recorded using the ERBI method. The motilities were studied during resting, after prostigmin 0.5 mg i.m. injection and after prifinium bromide 7.5 mg i.m. injection, with the following results: After prostigmin colonic motility of the proximal colon became significantly greater than that of the distal colon. Prifinium bromide inhibited the prostigmin-induced hypermotility markedly. It was demonstrated that this drug has an antispasmodic action not only on the distal colon but also on the proximal colon. Prifinium bromide was an antispasmodic drug which brought about a rapid effect which appears within 3 minutes after injection. The effect persisted for about 1 hour.