Hyperventilation is breathing that is deeper and more rapid than normal. It causes a decrease in the amount of a gas in the blood (called carbon dioxide, or CO2). This decrease may make you feel lightheaded, have a rapid heartbeat, and be short of breath. It also can lead to numbness or tingling in your hands or feet, anxiety, fainting, and sore chest muscles.

Some causes of sudden hyperventilation include anxiety, fever, some medicines, intense exercise, and emotional stress. Hyperventilation also can occur because of problems caused by asthma or emphysema or after a head injury. But it occurs most often in people who are nervous or tense, breathe shallowly, and have other medical conditions, such as lung diseases or panic disorder. Women experience hyperventilation more often than men. Most people who have problems with hyperventilation are 15 to 55 years old. Hyperventilation may occur when people travel to elevations over 6000 ft (2000 m). Symptoms can be similar to symptoms that are caused by another, more serious medical problem, such as a lung problem.

Acute (sudden) hyperventilation is usually triggered by acute stress, anxiety, or emotional upset. Chronic (recurring) hyperventilation may be an ongoing problem for people with other diseases, such as asthma, emphysema, or lung cancer.

Many women have problems with hyperventilation during pregnancy, but it usually goes away on its own after delivery.

In many cases, hyperventilation can be controlled by learning proper breathing techniques.

Symptoms of hyperventilation

Symptoms of hyperventilation usually last 20 to 30 minutes and may include:

• Feeling anxious, nervous, or tense.
• Frequent sighing or yawning.
• Feeling that you can't get enough air (air hunger) or need to sit up to breathe.
• A pounding and racing heartbeat.
• Problems with balance, lightheadedness, or vertigo.
• Numbness or tingling in the hands, feet, or around the mouth.
• Chest tightness, fullness, pressure, tenderness, or pain.

Other symptoms may occur less frequently, and you may not realize they are directly related to hyperventilation. These symptoms can include:

• Headache.
• Gas, bloating, or burping.
• Twitching.
• Sweating.
• Vision changes, such as blurred vision or tunnel vision.
• Problems with concentration or memory.
• Loss of consciousness (fainting).

Hyperventilation is not a disease, but you may need to be checked by your doctor if you have repeated episodes of hyperventilation symptoms. If you have recurring symptoms, you might be diagnosed with a condition called hyperventilation syndrome (HVS).

Treatment for hyperventilation depends on the cause. Home treatment is usually all that is needed for mild hyperventilation symptoms. Medical treatment may be needed for hyperventilation symptoms that are moderate to severe, that last for long periods of time, that come back, or that interfere with your daily activities. Medical treatment usually includes reassurance, stress reduction measures, breathing lessons, or medicine.

Check your symptoms to decide if and when you should see a doctor.