Acute behavioral effects and abuse potential of trazodone, zolpidem and triazolam in humans

The present study examined the acute behavioral effects and abuse potential of three drugs commonly used to treat sleep disorders, trazodone, zolpidem and triazolam, and placebo in ten male volunteers with histories of alcoho l and drug abuse. Trazodone (100, 200 and 300 mg), a triazolopyridine antid epressant, was included because antidepressants are being used more frequen tly to treat sleep disorders, but it is unclear whether they have a distinc t behavioral pharmacologic profile relative to benzodiazepine hypnotics. Zo lpidem (15, 30 and 45 mg), an imidazopyridine hypnotic, was tested because it is the most commonly prescribed hypnotic and purportedly has a unique be nzodiazepine-receptor binding profile. Triazolam (0.25, 0.5 and 0.75 mg), a triazolobenzodiazepine hypnotic, was included as the standard component be cause previous laboratory studies have demonstrated that it has at least so me abuse potential. Trazodone, zolpidem and triazolam generally produced co mparable dose-related increases in scores on the PCAG scale of the ARCI, wh ich suggests the doses tested were equivalent on some behavioral dimension. The effects of trazodone on subject-rated items thought to measure abuse p otential (e.g., subject ratings of Willing to Take Again) were less than th ose observed with triazolam. Zolpidem and triazolam produced comparable eff ects on these measures. The highest dose of zolpidem, but not triazolam, in creased ratings of Like Drug, Happy, Good Effects, friendly, Elated, Carefr ee and Bad Effects. Triazolam and zolpidem produced dose-dependent impairme nt on all of the performance tasks. Trazodone impaired performance on some, but not all, of these tasks. Consistent with the pharmacokinetics of these compounds, the time-action functions of trazodone, zolpidem and triazolam were similar on these measures. These data suggest that trazodone has less abuse potential than triazolam, and may be a viable alternative to benzodia zepine hypnotics in individuals with histories of alcohol or drug abuse. By contrast, despite its unique neuropharmacological profile, the acute behav ioral effects and abuse potential of zolpidem are comparable to those of tr iazolam.