Effects of 1 week administration of two benzodiazepines on the sleep and early daytime performance of normal subjects.
This study analyzed the effects of 1 week administration of alprazolam (AL; 0.25 mg), lorazepam (LO; 1 mg) and placebo (PL) on sleep as well as their residual effects on attention upon awakening. Under a crossed, double-blind design, six healthy male volunteer subjects between 19 and 30 years of age were studied. After two habituation sessions and a control session, each substance was given orally, twice a day for 7 days, with a 1-week washout period between administrations. At the end of each administration period, sleep studies were conducted from 2300 to 0700 hours. Evaluation of attention was carried out by means of a simple visuomotor reaction time (RT) task, and a time estimation (TE) task, that started at 0700 hours, lasting 1 h. Neither drug significantly affected any sleep variable. Both benzodiazepines tended to increase RT, but only LO did so significantly at the beginning of the attention test. No significant changes in predictive and failure responses during the RT task were produced by either drug. Also, no significant changes were observed in the TE. Even though only LO produced a significant increase of RT at the selected doses and with 1 week administration, it is suggested that both benzodiazepines could have residual effects on attention.
Jurado
J L
JL
Departamento de Cronobiología, Facultad de Psicologiía, U.N.A.M., Mexico City.
Fernández-Mas
R
R
Fernández-Guardiola
A
A
D000328:Adult; D000525:Alprazolam / Q000494:pharmacology*; D001288:Attention / Q000187:drug effects*; D006801:Humans; D008140:Lorazepam / Q000494:pharmacology*; D008297:Male; D011930:Reaction Time / Q000187:drug effects; D012890:Sleep / Q000187:drug effects*
D008140:Lorazepam; D000525:Alprazolam