opioida

Opioida are a class of drugs that act on opioid receptors in the nervous system. They include natural opiates such as morphine and codeine derived from the opium poppy, as well as semi-synthetic (for example heroin, oxycodone, hydrocodone) and synthetic opioids (for example fentanyl, methadone, tramadol). They modulate pain by binding primarily to mu‑opioid receptors, with additional activity at kappa and delta receptors, leading to analgesia, sedation, and mood alteration.

Medical use and forms: Opioida are used for acute and chronic pain relief, anesthesia, cough suppression, and, in some cases, treatment of opioid use disorder (for example methadone, buprenorphine). They can be given orally, by injection, or through transdermal patches or other routes. Dosing aims to balance analgesia with risk of adverse effects.

Risks: Common effects include respiratory depression, slowed heart rate, drowsiness, constipation, nausea, and pinpoint pupils. Tolerance can develop, requiring higher doses for the same effect, and physical dependence can lead to withdrawal upon cessation. Misuse and high-potency opioids, particularly fentanyl and its analogs, raise the risk of overdose and death. Reversal can be achieved with naloxone.

Regulation and public health: Opioida are controlled substances in most countries due to their potential for addiction and overdose. Policies emphasize prescription monitoring, risk assessment, and availability of addiction treatment and overdose prevention, including naloxone distribution and education.

History and overview: The opioids have a long history dating to opium use in ancient times, with morphine isolated in the 19th century and numerous synthetic opioids developed in the 20th and 21st centuries. The modern landscape includes medical use, substantial misuse, and ongoing public health challenges.