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Hyperventilation Overview

Hyperventilation is breathing in excess of what the body needs. This is sometimes called overbreathing. Rapid or deep breathing is sometimes seen in very serious conditions such as infection, bleeding, or heart attack.

Hyperventilation syndrome is more specific and relates to an overbreathing pattern that happens under certain conditions. This overbreathing results in a group of symptoms.

Although hyperventilation syndrome may seem very similar to panic attacks, the two disorders are different.

  • People with panic disorder often have emotional complaints (for example, fear of death or closed-in spaces) that accompany attacks.
  • If a person has hyperventilation syndrome, however, he or she will have certain symptoms without these emotional complaints (although the person still may be anxious).

Hyperventilation Causes

The cause or causes of hyperventilation syndrome are unknown. Certain conditions or situations produce overbreathing in some people.

Hyperventilation Symptoms

Sudden and everyday are the two forms of hyperventilation syndrome. In its everyday form, the overbreathing may be hard to detect. The sudden form comes on rapidly and has more intense symptoms. People with this syndrome may have stomach, chest, nervous system, and emotional complaints.

Hyperventilation syndrome may result in swallowing excessive air. This results in the following abdominal symptoms:

Also, anxiety with increased air movement through the mouth can cause a dry mouth feeling.

Chemical changes can happen with overbreathing. Hyperventilation causes the carbon dioxide level in the blood to decrease. This lower level of carbon dioxide reduces blood flow to the brain, which may result in the following nervous system and emotional symptoms:

  • Weakness
  • Fainting
  • Dizziness
  • Confusion
  • Agitation
  • A feeling of being outside yourself
  • Seeing images that aren't there
  • Feeling as if you can't breathe

Overbreathing can also cause the calcium levels to drop in your blood, which may result in the following nervous system symptoms:

  • Numbness and tingling (usually in both arms or around the mouth)
  • Spasms or cramps of the hands and feet
  • Muscle twitching

Many different factors can cause chest symptoms with hyperventilation syndrome. Normally, breathing is relaxed. If a person over breathes, the lungs become overinflated. Without thinking about it, the person might use the chest muscles to expand the rib cage. This extra muscle work will feel like shortness of breath, and the person will have difficulty taking a deep breath. The chest muscles will become tired, just like the legs tire after a long run. The lowered carbon dioxide levels in the blood can cause squeezing of the airways, which then results in wheezing. Hyperventilation syndrome may cause the following chest symptoms:

  • Chest pains or tenderness
  • Shortness of breath
  • Wheezing

The doctor will make sure that the person isn't suffering a heart attack by considering the following:

  • Hyperventilation symptoms usually last longer (hours as opposed to minutes).
  • Hyperventilation symptoms usually happen in younger people.
  • Hyperventilation symptoms usually improve with exercise.
  • Hyperventilation pain does not improve with heart medication.
  • In very rare cases, people who hyperventilate can have low carbon dioxide blood levels that can cause a spasm of the blood vessels that supply the heart. If a person already has heart disease, this spasm may be enough to cause a heart attack.
Last Reviewed 11/17/2017
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