Physostigmine in tricyclic antidepressant overdose.

Acute accidental and suicidal overdosages are becoming common in emergency medicine. Physostigmine salicylate (Antilirium) is the only parasympathomimetic drug capable of reversing both the central and peripheral manifestations of the anticholinergic syndrome caused by overdosage of tricyclic antidepressant drugs. Physostigmine acts rapidly, within 5 to 20 minutes, dramatically reversing the toxic effects. Because of the short duration of action, intoxication may recur and repeated doses may be necessary. Four cases, successfully managed, are presented and the pertinent literature reviewed.