Naloxone: effective in countering the effects of opiates

Naloxone is a complex polycyclic compound and the main morphine receptor antagonist. As such, it is used to counteract the effects of opiates on individuals.

Importance of Naloxone

In cases of acute morphine intoxication (especially overdose), naloxone is administered to displace morphine from its receptor sites and stop its action. It allows the comatose subject to wake up, except in cases of poly-intoxication.

Naloxone usually begins to be effective after two to three minutes. Naloxone remains active in the body for up to two hours after administration.

The administration of naloxone does not dispense with the need for medical follow-up of the intoxicated person. This is due to the limited life span of naloxone in the body. In fact, the lifespan of naloxone is equivalent to half that of morphine. Thus, after elimination of any trace of naloxone in the body of the subject, the traces of morphine still present in the body will resume their effect.


Administering naloxone to an unconscious person due to a non-opioid overdose is unlikely to cause more harm. Overdoses are life-threatening. It is better to administer naloxone than not to administer it.

The only time you would not administer naloxone to an overdose victim would be if there was a known history of allergy to naloxone or its ingredients. If you don’t know if the victim is allergic to naloxone (which is likely in a medical emergency), administer this medication.

Naloxone is a safe medication for people of all ages. It can temporarily counteract the effects of a potentially fatal opioid overdose. That’s why it can be used regardless of age, if you are pregnant or breastfeeding, or if you have heart or respiratory disease, or liver or kidney failure.