• Definition

    Drowsiness refers to feeling abnormally sleepy during the day. People who are drowsy may fall asleep in inappropriate situations or at inappropriate times.

    See also: Idiopathic hypersomnia

    Alternative Names

    Sleepiness - during the day; Hypersomnia; Somnolence


    Excessive daytime sleepiness (without a known cause) suggests that you have a significant sleep disorder. It is different from fatigue.

    Depression, anxiety, stress, and boredom can all contribute to excessive sleepiness, but these conditions more typically cause fatigue and apathy.

    Common Causes
    • Having to work long hours or different shifts (nights, weekends)
    • Medications (tranquilizers, sleeping pills, antihistamines)
    • Medical conditions (such as hypothyroidism, hypercalcemia, and hyponatremia /hypernatremia)
    • Not sleeping for long enough
    • Sleep disorders (such as sleep apnea syndrome and narcolepsy)