Purpose: This study was designed to identify a dose of alprazolam that would reduce anxiety associated with oral surgery without causing accompanying memory impairment.
Patients and methods: Thirty-six subjects in experiment 1 and 48 subjects in experiment 2 were pretested on a computerized memory battery to establish baseline performance. Subjects were then randomly assigned to receive placebo, 0.25 mg, or 0.75 mg oral alprazolam (experiment 1) or placebo, 0.25 mg, 0.50 mg, or 0.75 mg oral alprazolam (experiment 2). Forty-five minutes after the double-blind administration of alprazolam, subjects were given a second memory battery. The memory batteries tested story recall and recognition and word recall and recognition. Subjects in experiment 2 subsequently underwent oral surgery for the removal of one to four molars. The subjects completed anxiety questionnaires both before and after surgery.
Results: The 0.75-mg and 0.50-mg doses, but not the 0.25-mg dose, impaired word recall. The 0.75-mg dose also impaired story recall and recognition. The proportion of subjects reporting moderate to high anxiety during oral surgery decreased with increasing doses of alprazolam. Multiple regression indicated that the 0.75-mg alprazolam dose significantly decreased anxiety during oral surgery. The 0.25-mg and 0.50-mg doses also tended to reduce anxiety, but beta values for these doses did not reach significance.
Conclusions: These findings indicate that alprazolam produces memory impairment at the dosages necessary to produce clinically significant anxiolysis during oral surgery.