Effects of alprazolam on respiratory drive, anxiety, and dyspnea in chronic airflow obstruction: a case study.

Alprazolam, an anxiolytic benzodiazepine, has a pharmacologic profile similar to that of diazepam. An intermediate half-life of 10-12 hours and a comparatively brief duration of activity relative to other anxiolytic benzodiazepines justified evaluation of a 0.5-mg test dose in an anxious patient with chronic obstructive lung disease. Subjective indexes, breath-by-breath respiratory drive response to hypercapnia, and blood alprazolam concentrations were determined before and after dosing. Subjective testing included a visual analog dyspnea scale, the state anxiety inventory, and subjective feelings visual analog scales (represented by alertness, calmness, and level of contentment). After dosing, the patient was better able to tolerate the rebreathing study technique. Statistically significant improvements in dyspnea (t - 10.20; p 0.0005), anxiety (t - 45.85; p less than 0.0001), alertness (t - 13.04; p less than 0.0001), cententedness (t - 12.27; p less than 0.0001), and calmness (t - 8.05; p less than 0.0001) occurred after alprazolam administration. Drive to breathe, as determined by mouth occlusion pressure and minute ventilation, was not statistically different before and after dosing. No adverse effects were reported or observed. Further study is warranted.