Somnolence

Somnolence is a state of drowsiness or strong inclination to sleep, in which a person or animal is difficult to keep fully alert.

The word is used in clinical settings to describe sleepiness that goes beyond ordinary tiredness and that can interfere with daily function. It is assessed by observation and by questionnaires that rate how likely a person is to doze in different situations. Causes include sleep deprivation, sleep disorders, sedating medications, infections, and metabolic problems. In animals, owners notice excessive sleeping, slow responses, and reluctance to engage.

Somnolence was the most frequently reported adverse event in clinical trials of prescription cannabidiol and was more common in participants also taking clobazam, reflecting a drug interaction that raises the level of a sedating metabolite. Sleepiness has also been observed in some canine cannabinoid studies. Additive drowsiness with alcohol or sedating medications is a recognized concern. Anyone experiencing unexpected somnolence is advised to avoid driving and to discuss it with a clinician or, for pets, a veterinarian.