Naloxone

Abstract

Introduction and Definition: Naloxone is a “fast-acting medication used to temporarily reverse the effects of opioid overdoses […].^” It was approved for use by the Food and Drug Administration (FDA) in 1971; however, its mainstream use as a critical overdose antidote emerged between the 1990s and 2010s in response to the opioid crisis. It is most commonly available in the nasal spray form under the brand name Narcan.

Body: Naloxone is an opioid receptor antagonist, meaning it attaches to opioid receptor sites in the brain, displacing other opioid drugs (such as heroin, fentanyl and morphine) and stopping their effects (e.g. restoring slowed or stopped breathing). It can begin to take effect within two minutes, but is only active in the body for 30 to 120 minutes, which may be shorter than most opioids’ effects. As such, subsequent doses may be required. Naloxone may induce withdrawal symptoms in opioid-dependent individuals, but is safe for use in people of all ages, does not create dependence, and has no effect if no opioids are present. Naloxone will not reverse the effects of overdoses from non-opioid drugs.

Methods of Use: The FDA has approved two forms of naloxone delivery: injectable and nasal spray. If injected, naloxone is delivered intramuscularly, intravenously or subcutaneously. Injectable naloxone requires some needle training, making it less user-friendly than the nasal spray form. Prepackaged naloxone nasal spray is administered into one nostril. It is a needle-free alternative to the injectable naloxone medications, making it easier for bystanders or loved ones to administer without any training. Both forms are highly effective at reversing opioid overdoses and are often used by first responders in such cases.

Availability and Implications for Public Health: In Canada, take-home naloxone kits are now available without prescription at most pharmacies or harm reduction centers, and similar programs are in place worldwide. Studies have shown that the implementation of take-home naloxone programs has been cost-effective at reducing opioid overdose deaths and related morbidity. Such layperson interventions increase public awareness and knowledge, reducing stigma around naloxone as well as increasing overdose identification and recovery.