Naloxone
Naloxone is a potent opioid antagonist primarily used to reverse the effects of opioid overdose and intoxication. It works by displacing narcotics from the opioid receptors in the brain's central nervous system. Administered typically intravenously or via nasal spray, naloxone acts quickly, often within two minutes, but its effects last only 30 to 45 minutes, necessitating potential repeat doses in cases of prolonged opioid action. Research indicates that a significant majority of individuals receiving naloxone after an overdose survive the event, highlighting its effectiveness as an emergency treatment. Beyond emergency use, naloxone is also utilized in combination with buprenorphine, marketed as Suboxone, for treating opioid addiction. Community programs have emerged globally to distribute naloxone widely, empowering individuals to respond to overdose situations, and initiatives have encouraged its broader availability. While generally safe, naloxone can cause withdrawal symptoms in opioid-dependent users, underscoring the necessity for careful consideration in its administration. The promotion of naloxone use is a key element of harm reduction strategies aimed at addressing the opioid crisis.
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Subject Terms
Naloxone
- ALSO KNOWN AS: Narcan
DEFINITION: Naloxone, also commonly known by the Narcan brand name, is a synthetic opioid antagonist used as an antidote for opioid overdose. Naloxone reverses the life-threatening respiratory depression caused by natural and synthetic opioids, including heroin, morphine, propoxyphene, and methadone. Naloxone is not a controlled substance and was once only available by prescription. Beginning in 2014 and in response to the growing opioid epidemic in the United States, however, several pharmacies across the country began carrying the drug for sale over-the-counter.
Uses
Naloxone is a pure opioid antagonist that completely displaces narcotics from the opioid receptor sites in the brain's central nervous system. Naloxone is the treatment of choice for emergencies involving opioid overdose and intoxication. It is most often administered intravenously because of the need for a rapid onset of activity, but nasal naloxone is also effective in reversing the effects of an overdose. Naloxone’s effects are usually seen within two minutes of administration and last for thirty to forty-five minutes. Because opiates have a longer half-life than naloxone, repeat doses of naloxone may be necessary if complete reversal of opioid intoxication is not achieved. A study published in 2017 found that 93.5 percent of people given naloxone after an overdose survived that particular episode, and 84.3 percent were still alive a year later.
Naloxone combined with narcotic analgesic buprenorphine, with the brand name Suboxone, is also used to treat opiate addiction. Suboxone is available through specially licensed physicians as a facet of long-term maintenance therapy for opioid addiction, usually in an outpatient, office-based setting. In rare instances, naloxone may be used postoperatively to reverse the effects of anesthesia.
Naloxone/Narcan distribution programs have been implemented in cities worldwide to provide naloxone to opioid abusers and their acquaintances to be used in the case of an overdose. In the mid-2010s, there was a significant increase in the number of first responders in cities and towns throughout the United States who began carrying Narcan. These programs are critical components of harm reduction methodology and in reducing morbidity and mortality associated with opioid abuse. Some communities have examined the potential of making naloxone publicly available for anyone to administer to those suspected of overdosing.
In 2018, the US surgeon general issued a national advisory—the first issued by that office since 2005—to urge more Americans to carry naloxone with them
Precautions
Naloxone may cause increased heart rate, elevated blood pressure, and pulmonary edema, but these adverse effects do not usually warrant avoiding its use, given the life-threatening nature of opioid overdose. However, naloxone does precipitate immediate withdrawal symptoms in opioid-dependent persons.
Bibliography
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