Iunovar, a popular intravenous anesthetic, consists of a short-acting narcotic (fentanyl) and a long-acting tranquilizer (droperidol). It is associated with a number of undesirable side-effects, including respiratory depression, prolonged somnolence, and disorientation.1–3Respiratory depression is easily reversed with nalorphine or naloxone; however, there is no known antagonist for the somnolence and disorientation. Physostigmine is effective in reversing anticholinergic poisoning1–9and phenothiazine-induced coma.10It has been suggested that physostigmine might have nonspecific analeptic actions in the central nervous system and thus be of value as an antagonist to other CXS depressants.10This study was undertaken to evaluate physostigmine as an antagonist to somnolence and disorientation after Innovar-nitrous oxide anesthesia.