Bladder muscle contractility. Comparative effects and mechanisms of action of atropine, propantheline, flavoxate, and imipramine.

The anticholinergic and antispasmodic activity of atropine, propantheline, imipramine, and flavoxate were judged by each drug's ability to inhibit bethanechol chloride and barium chloride-induced canine detrusor contractions. In this in vitro model, atropine and propantheline are pure anticholinergic agents. Imipramine significantly decreases both bethanechol and barium-induced contractions, while flavoxate only minimally inhibits the response to either stimulant.