Acidosis is a condition in which there is too much acid in the body fluids. It is the opposite of alkalosis (a condition in which there is too much base in the body fluids).
The kidneys and lungs maintain the balance (proper pH level) of chemicals called acids and bases in the body. Acidosis occurs when acid builds up or when bicarbonate (a base) is lost. Acidosis is classified as either respiratory or metabolic acidosis.
Respiratory acidosis develops when there is too much carbon dioxide (an acid) in the body. This type of acidosis is usually caused when the body is unable to remove enough carbon dioxide through breathing. Other names for respiratory acidosis are hypercapnic acidosis and carbon dioxide acidosis. Causes of respiratory acidosis include:
- Chest deformities, such as kyphosis
- Chest injuries
- Chest muscle weakness
- Chronic lung disease
- Overuse of sedative drugs
Metabolic acidosis develops when too much acid is produced in the body. It can also occur when the kidneys cannot remove enough acid from the body. There are several types of metabolic acidosis:
- Diabetic acidosis (also called diabetic ketoacidosis and DKA) develops when substances called ketone bodies (which are acidic) build up during uncontrolled diabetes.
- Hyperchloremic acidosis is caused by the loss of too much sodium bicarbonate from the body, which can happen with severe diarrhea.
- Kidney disease (distal renal tubular acidosis and proximal renal tubular acidosis)
- Poisoning by aspirin, ethylene glycol (found in antifreeze), or methanol
- Severe dehydration
Lactic acidosis is a buildup of lactic acid. Lactic acid is mainly produced in muscle cells and red blood cells. It forms when the body breaks down carbohydrates to use for energy when oxygen levels are low. This can be caused by:
- Drinking too much alcohol
- Exercising vigorously for a very long time
- Liver failure
- Low blood sugar (hypoglycemia)
- Medications, such as salicylates
- MELAS (a very rare genetic mitochondrial disorder that affects energy production)
- Prolonged lack of oxygen from shock, heart failure, or severe anemia
- Sepsis -- severe illness due to infection with bacteria or other germs
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Strayer RJ. Acid-base disorders. In: Marx JA, Hockberger RS, Walls RM, et al, eds. Rosen's Emergency Medicine: Concepts and Clinical Practice. 8th ed. Philadelphia, PA: Elsevier Mosby; 2014:chap 124.