SLEEP CHANGES AFTER 4 CONSECUTIVE DAYS OF VENLAFAXINE ADMINISTRATION IN NORMAL VOLUNTEERS

Background: The purpose was to examine the effect of the antidepressan t drug venlafaxine on sleep architecture and periodic leg movements of sleep (PLMS) in normal volunteers. Method: Eight normal volunteers we re studied under laboratory sleep conditions as follows: 1 acclimatiza tion night, 1 baseline night, and 4 consecutive nights of venlafaxine p.o. administration (75 mg during the first 2 nights and 150 mg the la st 2 nights). Results: Venlafaxine increased both wake time and sleep stage I. Sleep stages II and III were reduced. REM sleep time was redu ced after the first venlafaxine dose, and, by the fourth night, REM sl eep was completely suppressed in all volunteers. Six of the eight volu nteers showed PLMS at a frequency above 25 per hour. Conclusion: Venla faxine produces several sleep disturbances, which include abnormal leg movements.