There are several important associations between the liver and acid-base balance. First, primarily because of its metabolism of certain cationic amino acids and organic acid anions, particularly lactate, the liver has a surprisingly important influence on normal acid-base homeostasis. Second, in the presence of the necessary pathogenic milieu, the liver may produce a life-threatening number of hydrogen ions. Examples include accelerated ketogenesis during insulinopenic states, or lactate production during severe hepatic parenchymal hypoxia. Third, patients with various types of liver disease, both acute and chronic, often develop complicating acid-base disturbances. In addition, liver disease may predispose the patient to a particular acid-base disorder such as phenformin-induced lactic acidosis. Finally, the acid-base disturbance may be a complication of therapy, as when diuretic therapy directed at ascites results in metabolic alkalosis.