alprazolam, drug used in the treatment of anxiety disorders and panic disorder. Alprazolam is classified as a benzodiazepine (a drug that produces a calming, sedative effect) and is marketed under the brand name Xanax by Pfizer, Inc.
Alprazolam was patented in the 1970s, having been developed by J.B. Hester at Upjohn Company (later part of Pfizer, Inc.). In 1981 it was approved by the U.S. Food and Drug Administration (FDA) for use in persons suffering from anxiety or from panic disorder. It is taken orally, generally in the form of a tablet, and is available in an extended-release formulation, enabling the drug to be made available to the body gradually after being taken and thereby reducing the frequency of administration.
Alprazolam exerts its effects by binding to a special site on the gamma-aminobutyric acid A (GABAA) receptor in the central nervous system. This binding action increases the receptor’s affinity to the inhibitory neurotransmitter GABA. Enhanced GABA activity reduces the transmission of neural impulses in the brain that are associated with anxiety and panic.
Alprazolam can cause a variety of side effects, some more serious than others. Examples of its mild side effects are dizziness, drowsiness, headache, nausea, and constipation. Serious side effects can include confusion, seizure, loss of coordination, and hallucinations. Alprazolam interacts with a number of other drugs, potentially increasing the risk of side effects, and the consumption of grapefruit and its juice should be avoided because of the effects of grapefruit on the metabolism of alprazolam. Dependence on alprazolam can occur, even in moderate dosages, and withdrawal symptoms may be present when the drug is stopped.