Attempts to attenuate the cardiostimulatory effects of ketamine

In an attempt to attenuate the cardiostimulatory effects of ketamine, a number of drugs were given individually, or in combination, to fit adults undergoing body surface operations, either before or aftera ketamine induction of 1 mg kg-1 followed by an infusion of 1 mg ml-1. Of these, practolol, phentolamine, practolol-phentolamine, phentolamine-practolol, promethazine, hexamethonium, procainamide and verapamil were unacceptable. Labetalol, in doses of 0.5 mg kg-1 and 1.0 mg kg-1, proved to be the most promising drug and is worthy of further study.