Hepatitis can be caused by: - Infections from parasites, bacteria, or viruses (such as Hepatitis A, B, or C viruses)
- Liver damage from alcohol, drugs, or poisonous mushrooms, which cause the liver to become inflamed
- An overdose of acetaminophen (such as Tylenol), which is rare but can be deadly
- Immune cells in the body attacking the liver and causing autoimmune hepatitis
Hepatitis may resolve quickly (acute hepatitis), or cause long-term disease (chronic hepatitis). In some instances, progressive liver damage or liver failure may result. The severity of hepatitis varies depending on many factors, including the cause of the liver damage and any underlying illnesses in a patient. Common risk factors include intravenous drug use, acetominophen overdose (the dose needed to cause damage is quite close to the effective dose, so be careful to take it only as directed), risky sexual behaviors, eating contaminated foods, and alcohol use. Common types of hepatitis include:
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