Hypersensitivity. Urinary retention. Uncontrolled narrow-angle glaucoma. Severe GI condition (including toxic megacolon & gastric retention). Myasthenia gravis. Patients undergoing haemodialysis. Severe hepatic impairment. Severe renal or moderate hepatic impairment. Patients on treatment w/ potent CYP3A4 inhibitor (eg, ketoconazole).