Yawning involves opening the mouth involuntarily while taking a long, deep breath of air. This is usually done as a result of drowsiness or weariness. Excessive yawning is yawning that happens more often than would be expected, even if drowsiness or weariness is present.

Yawning is a normal response to fatigue and drowsiness, but excessive yawning can be caused by a vasovagal reaction. This reaction is caused by the action of a nerve, called the vagus nerve, on the blood vessels. It may indicate a heart problem.

Normal yawning may happen when someone else yawns.

• Drowsiness or weariness
• Disorders associated with excessive daytime sleepiness
• Vasovagal reaction
  • Heart attack
  • Aortic dissection

Follow the treatment for the underlying cause.

• You experience unexplained and excessive yawning.
• The yawning is associated with excessive daytime sleepiness.

The health care provider will get your medical history and do a physical examination.

Medical history questions may include:

• When did the excessive yawning begin?
• How many times do you yawn per hour or day?
• Is the yawning the same throughout the day?
• Is it worse in the morning, after lunch, or during exercise?
• Is it worse in certain areas or certain rooms?
• Does yawning interfere with normal activities?
• Is the increased yawning related to the amount of sleep you get?
• Is it related to use of medications?
• Is it related to activity level?
• Is it related to boredom?
• What helps it?
• Does rest help?
• Does breathing deeply help?
• What other symptoms are present?
• What medications are you taking?

Hermanowicz N. Cranial nerves IX (glossopharyngeal) and X (vagus). In: Goetz CG, ed. Textbook of Clinical Neurology. 3rd ed. Philadelphia, Pa: Saunders Elsevier;2007:chap 13.

LeWinter MM. Pencardial diseases. In: Libby P, Bonow RO, Mann DL, Zipes DP, eds. Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine. 8th ed. Philadelphia, Pa: Saunders Elsevier;2007:chap 70.