Acidosis is a serious metabolic imbalance in which there is an excess of acidic molecules in the body.This can occur as a result of acid overproduction, impaired acid transport, acid underexcretion, or any combination. With overproduction, the body makes too much acid.This can occur in sepsis, a life-threatening widespread infection in which the body makes too much lactic acid. With underexcretion, the body is unable to rid itself of excess acid. This can occur in renal failure and various lung diseases.In renal failure, the kidneys are unable to cleanse the blood of acid.ith overproduction, the body makes too much acid. This can occur in sepsis, a life-threatening widespread infection in which the body makes too much lactic acid. With underexcretion, the body is unable to rid itself of excess acid. This can occur in renal failure and various lung diseases.