Health Illustrated Encyclopedia



Drowsiness refers to feeling abnormally sleepy during the day -- often with a strong tendency to actually fall asleep in inappropriate situations or at inappropriate times.

Alternative Names

Sleepiness - during the day; Hypersomnia; Somnolence


Excessive daytime sleepiness (without a known cause) suggests the presence of a significant sleep disorder and is different from fatigue. Although depression, anxiety, stress, and boredom can contribute to excessive sleepiness, these conditions more typically cause fatigue and apathy.


  • Having to work excessive hours or varying shifts (nights, weekends)
  • Medications (tranquilizers, sleeping pills, antihistamines)
  • Medical conditions (such as hypothyroidism, hypercalcemia, and hyponatremia/hypernatremia)
  • Self-imposed short sleep time
  • Sleep disorders (such as sleep apnea syndrome and narcolepsy)

Home Care

You can relieve drowsiness by treating the cause of the problem. For drowsiness due to depression, anxiety, boredom, or stress, try to solve problems without professional help first.

For drowsiness due to medications, talk to your health care provider about switching medications or discontinuing them. DO NOT CHANGE MEDICATIONS WITHOUT FIRST CONSULTING YOUR HEALTH CARE PROVIDER.

For drowsiness due to obesity and hypoventilation (reduced breathing), weight loss is recommended, and you should consult your health care provider.

Your health care provider can treat hypothyroidism, hypercalcemia, and hypo/hypernatremia.

For drowsiness due to narcolepsy, your doctor may prescribe stimulants (such as Ritalin).

For drowsiness due to other causes, seek medical help.

Consider buying a carbon monoxide monitor to check that the air in your home or apartment does not contain excessive levels of carbon monoxide.

When to Contact a Medical Professional

Contact your health care provider if:

  • You think the cause of your drowsiness is from any of the above conditions.

What to Expect at Your Office Visit

The doctor will examine you to determine the cause of your drowsiness. Your sleep patterns will be investigated, and you'll have a psychological profile taken.

You may be asked the following medical history questions about your drowsiness:

  • Sleep pattern
    • How well do you sleep?
    • How much do you sleep?
    • Do you snore?
    • Do you have episodes in which you do not breathe during sleep (sleep apnea)?
    • Do you fall asleep during the day when you are not intending to nap (such as when watching TV or reading)?
      • If so, do you awake feeling refreshed?
      • How often does this happen?
  • Emotional state
    • Are you depressed?
    • Are you anxious or feeling stressed?
    • Are you bored?
  • Other
    • What medications do you take?
    • What have you done to try to relieve the drowsiness?
    • How well did it work?
    • What other symptoms do you have?

Diagnostic tests that may be performed include:

After seeing your health care provider:

If your health care provider made a diagnosis related to drowsiness, you may want to note that diagnosis in your personal medical record.


Morgenthaler T, Kramer M, Alessi C, Friedman L, Boehlecke B, Brown T, et al. Practice parameters for the psychological and behavioral treatment of insomnia: an update. An American Academy of Sleep Medicine report. Sleep. 2006;29:1415-1419.

Schwartz JR, Roth T. Shift work sleep disorder: burden of illness and approaches to management. Drugs. 2006;66:2357-2370.

Provided by

Review Date: 10/31/2007
Reviewed By: Robert Hurd, M.D., Professor of Endocrinology, Department of Biology, Xavier University, Cincinnati, Ohio, and physician in the Primary Care Clinic, Cincinnati Veterans Administration Medical Center, Cincinnati, Ohio. Review provided by VeriMed Healthcare Network.
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