Acidosis is a condition in which there is excessive acid in the body fluids. It is the opposite of alkalosis (a condition in which there is excessive 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 acidosis 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 by a decreased ability to remove carbon dioxide from the body through effective 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
• Over-use of sedative drugs

Metabolic acidosis develops when too much acid is produced or 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 results from excessive loss of sodium bicarbonate from the body, as can happen with severe diarrhea.
• Lactic acidosis is a buildup of lactic acid. This can be caused by:
  • Alcohol
  • Cancer
  • Exercising vigorously for a very long time
  • Liver failure
  • Low blood sugar (hypoglycemia)
  • Medications such as salicylates
  • Prolonged lack of oxygen from shock, heart failure, or severe anemia
  • Seizures

Other causes of metabolic acidosis include:

• Kidney disease (distal renal tubular acidosis and proximal renal tubular acidosis)
• Poisoning by aspirin, ethylene glycol (found in antifreeze), or methanol
• Severe dehydration