Fentanyl, also spelled fentanil, is a highly potent synthetic piperidine opioid drug primarily used as an analgesic. Because fentanyl is 50 to 100 times more potent than morphine, its primary clinical utility is in pain management for cancer patients and those recovering from painful surgical operations. Fentanyl is also used as a sedative. Depending on the method of delivery, fentanyl can be very fast acting and ingesting a relatively small quantity can cause overdose.
Fentanyl works by activating mu-opioid receptors.
Fentanyl is also commonly known as fentanyl citrate, and is sold under the brand name Sublimaze among others.
Pharmaceutical fentanyl's adverse effects resemble those of other narcotic opioids, including addiction, confusion, respiratory depression (which, if extensive and untreated, may lead to arrest), drowsiness, nausea, visual disturbances, dyskinesia, hallucinations, delirium, a subset of the latter known as "narcotic delirium", analgesia, narcotic ileus, muscl