Acute behavioral effects of estazolam and triazolam in non-drug-abusing volunteers

The present study compared the acute behavioral, participant-rated and observer-rated effects of estazolam and triazolam in 7 healthy, non-drug-abusing humans. Placebo, estazolam (1, 2, and 4 mg), and triazolam (0.125, 0.25, and 0.50 mg) were administered orally in a double-blind, crossover design. Estazolam and triazolam produced orderly dose- and time-related impairment of learning and performance and produced sedative-like participant-rated and observer-rated effects. The absolute magnitude of estazolam's and triazolam's effects at peak effect was comparable across these measures. Triazolam, but not estazolam, impaired immediate and delayed picture recall. The greater effects of triazolam than of estazolam on immediate and delayed picture recall should be viewed cautiously because subtle differences between these drugs in terms of time-to-peak plasma levels may be a confound. Future research should attempt to more thoroughly establish the time-action function of estazolam and triazolam on tasks like picture recall and recognition and determine if the drugs differ at peak effect.