What it is
Difficulty staying awake or alert during normal waking hours — which may reflect inadequate sleep, medication effects, sleep disorders, or medical conditions requiring assessment.
Emerging evidence
Drowsiness
Difficulty staying awake or alert during normal waking hours — which may reflect inadequate sleep, medication effects, sleep disorders, or medical conditions requiring assessment.
CategoryNeurological
Reviewed by Internal Medical Editorial Team · Editorial Health Review
26 March 2026
At a glance
Drowsiness at a glance
Commonly experienced as
- Drowsiness creates a frustrating conflict between what one wants or needs to do and the body's insistence on sleep. In conditions like narcolepsy, this conflict is severe — sudden irresistible sleep attacks can occur in circumstances of any safety importance. More commonly, drowsiness represents the accumulated effects of inadequate or disrupted sleep on the alerting systems.
