A 15-patient randomized trial found quetiapine improved overnight sleep in adults with obstructive sleep apnea and insomnia but left them more impaired on morning driving tests than placebo.
At 50 mg before bed, the drug added more than 40 minutes of total sleep, cut wakefulness 45%, and reduced apnea events from 27 to 20 per hour.
Within 30 minutes of waking, participants on quetiapine showed more than triple the attention lapses and more lane swerving; 11 of 15 also reported greater sleepiness, though about one in four did not recognize their impairment.
One in three participants had mild to moderate side effects including nausea, restless legs and a blood-pressure drop on standing, and researchers advised avoiding driving or other safety-critical tasks for at least 9.5 hours after taking it.
The authors said the one-night laboratory study was too small to guide prescribing on its own, while outside experts urged larger follow-up studies, including on sex differences and risks for older adults.