The occurrence of undesirable events during the postictal electro-convulsive therapy (ECT) period was retrospectively compared between 29 patients who had received glycopyrrolate premedication 0.002 mg/lb i.v. and 25 patients who had received atropine 1.0 mg i.m. A separate comparison was made for 14 patients who had received ECTs with each of these premedications. A total of 952 ECTs were reviewed. In both comparisons supraventricular tachycardia was more common with atropine (p< .0001 with each), after —13% of ECTs. Otherwise, postictal events with the two agents were indistinguishable; specifically, bradycardia and nausea were not more frequent with glycopyrrolate.