Hepatitis is inflammation of the liver. Inflammation, or swelling, occurs when the tissues are damaged or diseased. This swelling can damage and impair your liver's functioning. Hepatitis can either be acute (short-term) or chronic (long-term). There are several forms of hepatitis, each with its own set of causes: The most frequent form is viral hepatitis. Hepatitis A, B, C, D, and E are the five major viral classifications of hepatitis. Each kind of virus causes a distinct type of hepatitis. A, B, and C are the most common. Heavy alcohol use causes alcoholic hepatitis. Specific poisons, chemicals, drugs, or supplements can induce toxic hepatitis. Autoimmune hepatitis or autoimmune liver disease is a chronic condition in which your body produces antibodies against your liver tissue. Although the origin is unknown, genetics and your environment may have a role. If your doctor suspects you have hepatitis, blood testing can determine whether you have type A, B, C, or D.