Respiratory alkalosis is a condition marked by a low level of carbon dioxide in the blood due to breathing excessively.
Common causes include:
- Anxiety or panic
- Overbreathing (hyperventilation)
- Pregnancy (this is normal)
- Severe anemia
- Liver disease
- Overdose of certain medicines, such as salicylates, progesterone
Any lung disease that leads to shortness of breath can also cause respiratory alkalosis (such as pulmonary embolism and asthma).
The symptoms may include:
- Numbness of the hands and feet
- Chest discomfort
Your health care provider will perform a physical exam. Tests that may be done include:
- Arterial blood gas, which measures oxygen and carbon dioxide levels in the blood
- Basic metabolic panel
- Chest x-ray
- Pulmonary function tests to measure breathing and how well the lungs are functioning
Treatment is aimed at the condition that causes respiratory alkalosis. Breathing into a paper bag — or using a mask that causes you to re-breathe carbon dioxide — sometimes helps reduce symptoms when anxiety is the main cause of the condition.
Outlook depends on the condition that is causing the respiratory alkalosis.
Seizures may occur if the alkalosis is extremely severe. This is very rare.
Call your provider if you have any symptoms of lung disease, such as long-term (chronic) cough or shortness of breath.
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Seifter JL. Acid-base disorders. In: Goldman L, Schafer AI, eds. Goldman-Cecil Medicine. 25th ed. Philadelphia, PA: Elsevier Saunders; 2016:chap 118.
Strayer RJ. Acid-base disorders. In: Walls RM, Hockberger RS, Gausche-Hill M, eds. Rosen’s Emergency Medicine: Concepts and Clinical Practice. 9th ed. Philadelphia, PA: Elsevier; 2018:chap 116.