fentanyl
n. a highly potent opioid analgesic that is used for anesthesia during surgery, for the management of severe cancer pain in patients resistant to other opioids, and (as a lozenge or sucker) for the relief of severe anxiety in children prior to surgical procedures. Its toxicity is similar to that of other opioids, with respiratory and circulatory depression predominating. It is known as China white in illicit use. Analogs of fentanyl in current use include sufentanil, alfentanil (U.S. trade name: Alfenta), and remifentanil (U.S. trade name: Ultiva). U.S. trade names: Sublimaze (injectable form); Actiq, Fentora, and Oralet (oral forms); Duragesic (transdermal form, i.e., applied to the skin).