Intralingual naloxone reversal of morphine-induced respiratory depression in dogs.

A descriptive study was done to determine whether naloxone is efficacious in reversing morphine-induced respiratory depression in dogs when administered intralingually into the ventral lateral surface of the tongue. Mean minute ventilation was depressed to half of resting baseline levels using fixed intravenous doses of morphine sulfate. Intralingually administered naloxone reversed this respiratory depression rapidly within one minute, and resulted in a greater than fourfold increase in mean minute ventilation above established baseline levels.