Antagonists of morphine-induced respiratory depression. A study in postoperative patients

This double blind study showed the effect of four drugs, levallorphan, naloxone, doxapram and amiphenazole, an opiate-induced analgesia and respiratory depression. Satisfactory analgesia was induced by administration of morphine intravenously in a dose of up to 0.33 mg/kg; such a dose, however, produced significant depression of respiration. Administration of levallorphan, naloxone, and amiphenazole produced reversal of respiratory depression and analgesia. Doxapram reversed the respiratory depression but did not alter analgesia.