Alprazolam, sold under the brand name Xanax among others, is a fast-acting, potent tranquilizer of moderate duration within the triazolobenzodiazepine group of chemicals called benzodiazepines.

[14][16] Alprazolam was invented by Jackson Hester Jr. at the Upjohn Company[20] and patented in 1971 and approved for medical use in the United States in 1981.

[9] In Australia, alprazolam is not recommended for the treatment of panic disorder because of concerns regarding tolerance, dependence, and abuse.

[9] Alprazolam is recommended by the World Federation of Societies of Biological Psychiatry (WFSBP) for treatment-resistant cases of panic disorder where there is no history of tolerance or dependence.

[30] Alprazolam should be avoided or carefully monitored by medical professionals in individuals with myasthenia gravis, acute narrow-angle glaucoma, severe liver deficiencies such as cirrhosis, severe sleep apnea, pre-existing respiratory depression, marked neuromuscular respiratory, acute pulmonary insufficiency, chronic psychosis, hypersensitivity, allergy to alprazolam or other benzodiazepines, and borderline personality disorder, where it may induce suicidality and dyscontrol.

[31][32][33] Like all central nervous system depressants, alprazolam in larger-than-normal doses can cause significant deterioration in alertness and increase drowsiness, especially in those unaccustomed to the drug's effects.

[35] Possible side effects include: In September 2020, the U.S. Food and Drug Administration (FDA) required that boxed warnings for all benzodiazepine medications be updated to describe the risks of abuse, misuse, addiction, physical dependence, and withdrawal reactions consistently across all the medicines in the class.

[52] Combining CYP3A4 inhibitors such as cimetidine, erythromycin, norfluoxetine, fluvoxamine, itraconazole, ketoconazole, nefazodone, propoxyphene, and ritonavir delay the hepatic clearance of alprazolam, which may result in its accumulation[53] and increased severity of its side effects.

[57] Plants in the genus Hypericum, including St. John's wort, conversely can lower the plasma levels of alprazolam and reduce its therapeutic effect.

[9] The use of alprazolam during pregnancy is associated with congenital abnormalities,[9][61] and use in the last trimester may cause fetal drug dependence and withdrawal symptoms in the post-natal period as well as neonatal flaccidity and respiratory problems.

[62][63] However, in long-term users of benzodiazepines, abrupt discontinuation due to concerns of teratogenesis has a high risk of causing extreme withdrawal symptoms and a severe rebound effect of the underlying mental health disorder.

[42] The potential for misuse among those taking it for medical reasons is controversial, with some expert reviews stating that the risk is low and similar to that of other benzodiazepine drugs.

[14][25] Compared to the large number of prescriptions, relatively few individuals increase their dose on their own initiative or engage in drug-seeking behavior.

[74] Some common symptoms of alprazolam discontinuation include malaise, weakness, insomnia, tachycardia, lightheadedness, and dizziness.

[79] The benzodiazepines diazepam and oxazepam have been found to produce fewer withdrawal reactions than alprazolam, temazepam, or lorazepam.

When GABA binds the GABAA receptor the channel opens and chloride enters the cell which makes it more resistant to depolarisation.

[90] Giving alprazolam, as compared to lorazepam, has been demonstrated to elicit a statistically significant increase in extracellular dopamine D1 and D2 concentrations in the striatum.

Blood or plasma alprazolam concentrations are usually in a range of 10–100 μg/L in persons receiving the drug therapeutically, 100–300 μg/L in those arrested for impaired driving, and 300–2,000 μg/L in victims of acute overdosage.

Most of the commercial immunoassays used for the benzodiazepine class of drugs cross-react with alprazolam, but confirmation and quantitative determination are usually done by chromatographic techniques.

[25] Despite this, most prescribed alprazolam users do not use their medication recreationally, and the long-term use of benzodiazepines does not generally correlate with the need for dose escalation.

[112] However, based on US findings from the Treatment Episode Data Set (TEDS), an annual compilation of patient characteristics in substance abuse treatment facilities in the United States, admissions due to "primary tranquilizer" (including, but not limited to, benzodiazepine-type) drug use increased 79% from 1992 to 2002, suggesting that misuse of benzodiazepines may be on the rise.

[113] The Centers for Disease Control and Prevention (CDC) reported an 89 percent increase in emergency room visits nationwide related to nonmedical benzodiazepine use between 2004 and 2008.

[116][117] A large-scale nationwide U.S. government study conducted by the Substance Abuse and Mental Health Services Administration concluded that, in the US, benzodiazepines are recreationally the most frequently used pharmaceuticals due to their widespread availability, accounting for 35% of all drug-related visits to hospital emergency and urgent care facilities.

[126] Due to the low weight of a dose, alprazolam, in one case, was distributed on blotter paper in a manner similar to LSD.

[128] Alprazolam has typically caused anterograde amnesia effects (inability to recall new events), but a study conducted on mice by the Department of Pharmaceutical Sciences and Drug Research at Punjabi University has also determined that alprazolam can produce retrograde amnesic effects (inability to remember events occurring before amnesia).

One 2016 study found that "chronic administration of alprazolam affects memory but attentive and psychomotor performance remained unaffected".

[128] Similarly, a 2017 meta-analysis concluded that "a range of neuropsychological functions are impaired as a result of long-term benzodiazepine use, and that these are likely to persist even following withdrawal".

Some of the more common terms are modified versions of the trade name "Xanax", such as Xannies (or Xanies) and the phonetic equivalent of Zannies;[131][132] references to their drug classes, such as benzos or downers; or remark upon their shape or color (most commonly a straight, perforated tablet or an oval-shaped pill): bars, ladders, Xanbars, Xans, Z-bars, handlebars, beans, footballs, planks, poles, sticks, blues, or blue footballs.