Metabolic acidosis is a condition that occurs when the body produces excessive quantities of acid. This occurs when acid builds up within the body because it is not being removed by the kidneys, or when the body doesn't have enough base to offset a normal amount of acid.

The underlying causes of metabolic acidosis are many and diverse. When the body burns fat instead of carbohydrates as fuel, the body produces acidic ketones as found in diabetics, chronic alcohol abusers and people on severely restricted diets.  The body produces lactic acid when it has a scarcity of usable oxygen, typically during intense exercise, when the patient has a sudden drop in blood pressure, has heart failure, or an overwhelming infection. Some kidney diseases and some immune system and genetic disorders can damage the kidneys which also causes acid levels to rise. Severe diarrhea and laxative abuse can also lower levels of bicarbonate which helps neutralize acids in the blood. 

A wide range of symptoms are associated with metabolic acidosis including chest pain, palpitations, headache, blurred vision, nausea, vomiting, abdominal pain, muscle weakness, bone and joint pain, altered appetite and weight gain. Patients may also experience changes in their mental state, particularly severe anxiety or confusion, and exhibit deep, rapid breathing. Metabolic acidosis can cause normal chemical reactions and processes in the body to fail to function correctly, which can have serious consequences, including neurological and cardiac complications, which may result in coma and death. Long-term chronic metabolic acidosis can also lead to osteoporosis and can cause fractures.

Treatment for metabolic acidosis involves treating whatever has caused it in order to restore the balance of acid in the body. This includes detoxification if the patient has alcohol or drug poisoning, giving fluids intravenously to combat dehydration in diabetics, and administering sodium bicarbonate orally or intravenously.