Jane S. Ricciuti, RPh, MS


February 19, 2003

In This Article

Central Nervous System Agents

Xanax XR
(alprazolam) Extended-release Tablets

Manufacturer: Pharmacia & Upjohn

Drug Approval Classification: Original NDA (approval date: 1/17/03)

Indication: Xanax XR, a new extended-release form of Xanax (alprazolam), was approved. Xanax XR is indicated for the treatment of panic disorder, with or without agoraphobia.

Panic disorder (DSM-IV) is characterized by recurrent unexpected panic attacks, ie, a discrete period of intense fear or discomfort in which 4 (or more) of the following symptoms develop abruptly and reach a peak within 10 minutes:

palpitations, pounding heart, or accelerated heart rate;

  • sweating;

  • trembling or shaking;

  • sensations of shortness of breath or smothering;

  • feeling of choking;

  • chest pain or discomfort;

  • nausea or abdominal distress;

  • feeling dizzy, unsteady, lightheaded, or faint;

  • derealization (feelings of unreality) or depersonalization (being detached from oneself);

  • fear of losing control;

  • fear of dying;

  • paresthesias (numbness or tingling sensations);

  • chills or hot flushes.

  • The longer-term efficacy of Xanax XR has not been systematically evaluated. Thus, the physician who elects to use this drug for periods longer than 8 weeks should periodically reassess the usefulness of the drug for the individual patient.

    Dosing: The recommended dose of Xanax XR is 1 tablet daily. Tablets should be taken intact; they should not be chewed, crushed, or broken.

    The suggested total daily dose ranges from 3 to 6 mg/day. Dosage should be individualized for maximum beneficial effect.

    Xanax XR is available in 0.5-mg, 1-mg, 2-mg, and 3-mg extended-release tablets.

    Dose titration is recommended at intervals of 3 to 4 days in increments of no more than 1 mg/day. Dose reductions should be in increments of 0.5 mg every 3 days.

    Patients who are currently being treated with divided doses of Xanax (immediate-release) tablets may be switched to Xanax XR tablets at the same total daily dose taken once daily.

    Clinical Summary: Patients with panic disorder were enrolled in two 6-week, placebo-controlled studies. Efficacy was based on the change in multiple measures of panic attack frequency. The mean dose was 4.2 mg/day and 4.6 mg/day, respectively, in each study. Efficacy beyond 6 weeks has not been established.

    Adverse Effects: Most frequent adverse events were similar to those seen with immediate-release alprazolam; they include sedation, somnolence, and memory impairment.

    Pharmacokinetics: Xanax XR maintains a constant concentration for 5 to 11 hours after dosing. A high-fat meal given up to 2 hours before dosing with Xanax XR tablets increased the mean Cmax by about 25%. The effect of this meal on Tmax depended on the timing of the meal, with a reduction in Tmax by about one third for subjects eating immediately before dosing and an increase in Tmax by about one third for subjects eating 1 hour or more after dosing.

    Xanax XR (alprazolam) Extended-release Tablets Labeling

    Xanax XR (alprazolam) Extended-release Tablets


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