Naloxone, an opioid antagonist, cannot be administered orally because the liver metabolizes the first dose and there is little drug that reaches the circulation (first-pass effect). Naloxone is well absorbed IM, SQ, and endotracheally. The onset of action is one-two minutes following IV administration. Duration of action is 20-90 minutes.
Heroin abuse is not a major problem in this state, so I am not going to address the administration of naloxone and possible precipitation of narcotic withdrawal.
Naloxone should be administered to all patients with a decreased sensorium. Although pediatricians are accustomed to administering drugs on a meticulous mg/kg dose, naloxone should not be administered in this fashion. One is attempting to reverse the effect of a receptor, do dose-response does not apply. When naloxone is administered, a minimum of 2mg (not 0.2) should be given. If there is no response, one should consider giving 6-8 more milligrams. The toxicity of opiates and some nonopiate drugs may be reversed by the administration of hi-dose naloxone. Some nonopiate drugs may cause the release of endogenous endorphins or there may be receptor cross-reactivity. Clinical effects of methadone, Darvon, Demerol, Lomotil, clonidine, valproate, ace inhibitors, and benzodiazepines, have improved following the administration of high- dose naloxone.
There are no side effects of high-dose naloxone administration to children. It is not an analeptic and does not cause hypertension.