opioid analgesic

Opioid analgesics are a class of drugs derived from the opium poppy, widely used for pain relief and sedation. These drugs, including prescription medications like fentanyl and oxycodone, as well as illegal substances like heroin, act on opioid receptors in the brain. This interaction produces effects such as pain reduction and euphoria, but also carries a high risk of addiction, medically termed opioid use disorder.1

Opioids are classified as narcotics and can be agonists, partial agonists, or antagonists, depending on how they interact with receptors. Historically, opium has been used for millennia, with morphine isolated in the early 19th century, followed by the development of synthetic substitutes like meperidine and methadone. While effective for severe pain, opioid use can lead to tolerance, physical dependence, and potentially fatal overdose, which can be treated with naloxone.1