Definition of Hepatitis:

Hepatitis is inflammation of the liver.

Causes, incidence, and risk factors:

The disease can be caused by:

• Infections from viruses (such as hepatitis A, B, or C), bacteria, or parasites
• Liver damage from alcohol, drugs, or poisonous mushrooms
• An overdose of acetaminophen, which can be deadly
• Immune cells in the body attacking the liver and causing autoimmune hepatitis

Medications that can cause damage to the liver include methyldopa (used uncommonly for high blood pressure), isoniazid for tuberculosis, seizure medications (like valproate and phenytoin), chlorpromazine, amiodarone (for irregular heart rhythm), and certain antibiotics (including trimethoprim-sulfamethoxazole and erythromycin). If you need to take any of these, your doctor may need to check your liver function.

Liver disease can also be caused by inherited disorders such as cystic fibrosis and Wilson's disease, a condition that involves having too much copper in your body (the excess copper deposits in the liver).

Hepatitis may start and resolve quickly (acute hepatitis), or cause long-term disease (chronic hepatitis). In some instances, progressive liver damage, liver failure, or even liver cancer may result.

The severity of hepatitis depends on many factors, including the cause of the liver damage and any underlying illnesses you have. Hepatitis A, for example, is generally short-lived, not leading to chronic liver problems.

Common risk factors include:

• Intravenous drug use
• Overdosing on acetaminophen -- the dose needed to cause damage is close to the effective dose, so be careful to take it only as directed -- ask your doctor what amount of acetaminophen is safe for you; if your liver disease is severe, your doctor may also tell you to avoid certain anti-inflammatory medicines
• Engaging in risky sexual behaviors (like having multiple sexual partners and unprotected intercourse)
• Eating contaminated foods
• Traveling to an area where certain diseases are common
• Living in a nursing home or rehabilitation center
• Having a family member who recently had hepatitis A
• Using or abusing alcohol
• Being an organ transplant recipient
• Having HIV or AIDS
• Having received a blood transfusion before 1990 (hepatitis C blood test was not available)
• Being a newborn of a mother with hepatitis B or C (can be transmitted during delivery)
• Being a healthcare worker, including dentist and dental hygienist, because of blood contact
• Receiving a tattoo

See also:

• Alcoholic hepatitis
• Autoimmune hepatitis
• Delta agent (hepatitis D)
• Drug-induced hepatitis
• Hepatitis A
• Hepatitis B
• Hepatitis C