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CNN's Sanjay Gupta investigates if Naloxone, a drug that can reverse an overdose can also help end the overdose epidemic.

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Naloxone - Clinical Pharmacology         Read More about Naloxone

Complete or Partial Reversal of Opioid Depression

Naloxone prevents or reverses the effects of opioids including respiratory depression, sedation and hypotension. Also, Naloxone can reverse the psychotomimetic and dysphoric effects of agonist-antagonists, such as pentazocine.

Naloxone is an essentially pure opioid antagonist, i.e., it does not possess the “agonistic” or morphine-like properties characteristic of other opioid antagonists. When administered in usual doses and in the absence of opioids or agonistic effects of other opioid antagonists, it exhibits essentially no pharmacologic activity.

Naloxone has not been shown to produce tolerance or cause physical or psychological dependence. In the presence of physical dependence on opioids, Naloxone will produce withdrawal symptoms. However, in the presence of opioid dependence, opiate withdrawal symptoms may appear within minutes of Naloxone administration and will subside in about 2 hours. The severity and duration of the withdrawal syndrome are related to the dose of Naloxone and to the degree and type of opioid dependence.

While the mechanism of action of Naloxone is not fully understood, in vitro evidence suggests that Naloxone antagonizes opioid effects by competing for the mu, kappa, and sigma opiate receptor sites in the CNS, with the greatest affinity for the mu receptor.

When Naloxone hydrochloride is administered intravenously, the onset of action is generally apparent within two minutes; the onset of action is slightly less rapid when it is administered subcutaneously or intramuscularly. The duration of action is dependent upon the dose and route of administration of Naloxone hydrochloride. Intramuscular administration produces a more prolonged effect than intravenous administration. Since the duration of action of Naloxone may be shorter than that of some opiates, the effects of the opiate may return as the effects of Naloxone dissipates. The requirement for repeat doses of Naloxone, however, will also be dependent upon the amount, type and route of administration of the opioid being antagonized.