Hyperventilation is rapid or deep breathing that can occur with anxiety or panic. It is also called overbreathing, and may leave you feeling breathless.

See also: Rapid shallow breathing

When you breathe, you inhale oxygen and exhale carbon dioxide. Excessive breathing leads to low levels of carbon dioxide in your blood. This causes many of the symptoms you may feel if you hyperventilate.

Feeling very anxious or having a panic attack are the usual reasons that you may hyperventilate. However, rapid breathing may be a symptom of a disease, such as:

• Bleeding
• Heart or lung disorder
• Infection

Your doctor will determine the cause of your hyperventilation. Rapid breathing may be a medical emergency -- unless you have experienced this before and have been reassured by your doctor that your hyperventilation can be self treated.

Often, panic and hyperventilation become a vicious cycle. Panic leads to rapid breathing, and breathing rapidly can make you feel panicked.

If you frequently overbreathe, you may have hyperventilation syndrome that is triggered by emotions of stress, anxiety, depression, or anger. Occasional hyperventilation from panic is generally related to a specific fear or phobia, such as a fear of heights, dying, or closed-in spaces (claustrophobia).

If you have hyperventilation syndrome, you might not be aware you are breathing fast. However, you will be aware of having many of the other symptoms, including:

• Belching
• Bloating
• Chest pain
• Confusion
• Dizziness
• Dry mouth
• Light-headedness
• Muscle spasms in hands and feet
• Numbness and tingling in the arms or around the mouth
• Palpitations
• Shortness of breath
• Sleep disturbances
• Weakness

• Anxiety and nervousness
• Bleeding
• Cardiac disease, such as congestive heart failure or heart attack
• Drugs (such as an aspirin overdose)
• Infection such as pneumonia or sepsis
• Ketoacidosis and similar medical conditions
• Lung disease such as asthma, chronic obstructive pulmonary disease (COPD), or pulmonary embolism
• Panic attack
• Pregnancy
• Severe pain
• Situations where there is a psychological advantage in having a sudden, dramatic illness (for example, somatization disorder)
• Stimulant use
• Stress