Alprazolam

Alprazolam is a short- to intermediate-acting benzodiazepine used primarily as an anxiolytic. It acts as a positive allosteric modulator of the gamma-aminobutyric acid A (GABA-A) receptor, enhancing the inhibitory effects of GABA on neuronal activity. This produces relief of anxiety, with sedative, anticonvulsant, and muscle-relaxant properties. It is approved for generalized anxiety disorder and panic disorder (with or without agoraphobia). It is sometimes used off-label for short-term relief of severe anxiety or acute stress-related symptoms, but long-term use is generally discouraged.

Pharmacokinetics and metabolism: Alprazolam is rapidly absorbed after oral administration, with onset of action often within 15 to 30 minutes and peak plasma concentrations in about 1 to 2 hours. The elimination half-life in adults ranges roughly from 6 to 20 hours, leading to relatively rapid but variable clearance. It is extensively metabolized in the liver, mainly by the CYP3A4 system, to active and inactive metabolites, and is excreted in urine and feces. Drug interactions with CYP3A4 inhibitors or inducers can significantly alter exposure.

Dosing and duration: Treatment is typically initiated at a low dose and titrated based on response and tolerability. Because of the risk of dependence and withdrawal, alprazolam is generally recommended for the shortest duration feasible, often with careful monitoring. Common adverse effects include drowsiness, dizziness, fatigue, and impaired coordination; cognitive slowing and confusion can occur, especially in older adults. Alcohol or other central nervous system depressants can markedly increase sedation and risk.

Special considerations: Contraindications include hypersensitivity to the drug, acute narrow-angle glaucoma, and certain severe liver conditions. Use in pregnancy or lactation is generally avoided unless benefits outweigh risks. Alprazolam is a Schedule IV controlled substance in many jurisdictions due to potential misuse and dependence.