Fentanyl is a potent synthetic opioid drug primarily used as an analgesic (pain reliever) and anesthetic. It is approximately 50 to 100 times more potent than morphine and about 50 times more potent than heroin in its analgesic effects

. It acts mainly at the µ-opioid receptor to produce pain relief, sedation, euphoria, and respiratory depression

. Medically, fentanyl is prescribed to treat severe pain, such as pain after surgery or chronic pain in patients tolerant to other opioids. It is available in forms such as injections, transdermal patches, and lozenges

. Illegally manufactured fentanyl is often found as powder, pills, or mixed with other drugs, contributing to overdose risks due to its high potency

. In summary, fentanyl is a synthetic opioid analgesic and anesthetic known for its extreme potency and high risk of overdose when misused