Ineffective Over Time

Alprazolam was approved by the FDA based on data showing it to be effective over a period of four weeks. Subsequent studies showed that Alprazolam lost its efficacy by week eight,^[1,2] with significant rebound anxiety and other symptoms following discontinuation,^[3] yet the label still allows use up to 4 months. A longer-term study (detailed in the Efficacy page) showed a loss of efficacy by week 8, while alternative treatments retained their efficacy. The FDA’s “Alprazolam Evaluation Results” starts off by stating that alprazolam is not significantly different from other benzodiazepines: “The types, rates and severity of treatment-emergent and drug discontinuation-emergent adverse events observed with alprazolam-XR were similar to those observed with alprazolam-IR and other benzodiazepines.”^[4]  There are no published long-term efficacy studies for most of the other benzodiazepines and Z-drugs.

[1] Ballenger. Alprazolam in panic disorder, agoraphobia. Arch Gen Psych. 1988;45:413-22

[2] Noyes. Alprazolam in panic disorder, agoraphobia. Arch Gen Psych. 1988;45:423-28

[3] Pecknold. Alprazolam in panic disorder, agoraphobia. Arch Gen Psych.  1988;45:429-36

[4] FDA, The Center for Drug Evaluation and Research Approval Package for:  Application Number 21-434, Review and Evaluation of Clinical Data, Alprazolam Evaluation Results (Xanax-XR) for the Treatment [redacted] Panic Disorder with or without Agoraphobia”, approved on 10/16/2002.