Naloxone Does Not Antagonize General Anesthesia in the Rat

Abstract

The administration of naloxone 2, 10, 50 or 250 mg/kg i.v. did not alter halothane requirement in Spraque-Dawley rats (12 rats/group). Two rats convulsed when given 50 mg/kg while anesthetized with halothane. In a separate group of awake rats, 7 of 9 animals convulsed when given naloxone, 100 mg/kg. Any effect of naloxone on anesthetic requirement must be small, and that if an effect exists it is the result of a nonspecific analeptic action of naloxone rather than a specific action at opiate receptors.