Propantheline as a diagnostic tool--a serious complication

Propantheline bromide is a synthetic quaternary ammonium compound widely used in urologic patients to block the action of acetylcholine at the postganglionic nerve endings of the bladder's parasympathetic innervation. It is used clinically in a wide range of doses in ambulatory outpatients as well as hospitalized patients. To document its effects on the bladder, test doses are given with a cystometrogram documenting the dynamic changes. Herein we report a case of serious cardiac toxicity from a diagnostic test dose.