Alprazolam

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Alprazolam, is an anxiolytic benzodiazepine used to treat anxiety disorders. It is sold under several brand names such as Xanax, Xanor and Tafil.

Alprazolam has a calming effect, with potential side effects of drowsiness, clumsiness, fatigue, and headache. The drug can also have more severe side effects, such as blurred vision, slurred speech, and changes in normal behavior. The drug is habituating, and users develop a tolerance. Physical and psychological dependence after several months of alprazolam treatment is common. As a result, long-term alprazolam treatment cannot be abruptly terminated, but must instead be slowly reduced in dosage over a course of weeks (as is the case with many drugs operating on neurotransmitters). Abrupt cessation may cause rebound anxiety, insomnia, and seizures, among other symptoms.

For more long-term relief of anxiety, selective serotonin reuptake inhibitor medicines such as paroxetine, sertraline, or fluoxetine are often prescribed.

In the United States, the sale of alprazolam is regulated by the Food and Drug Administration, and requires a doctor's prescription. Alprazolam has been associated with both physical and psychological dependency.

Mechanism of action

Alprazolam is a benzodiazepine, with a triazolo-ring attached to its structure. Alprazolam binds to the GABA receptor GABA_A, causing a conformational change and thus increasing inhibitory effects of GABA. Unlike other benzodiazepines, alprazolam has also some antidepressant activity.

Pharmacokinetics

Alprazolam is readily absorbed from the gastrointestinal tract. The peak plasma concentration is achieved in 1-2 hours. Most of the drug is bound to plasma protein, mainly albumin. Alprazolam is hydroxylated in the liver to α-hydroxyalprazolam, which is also active. This and other metabolites are later excreted in urine as glucuronides. Some of alprazolam is also excreted in unchanged form.