What Is Fulminant Hepatitis?

Medically Reviewed by Sabrina Felson, MD on March 04, 2024
5 min read

Fulminant hepatitis is when your liver begins to fail very quickly within days or weeks, depending on the cause. This sudden liver failure can happen in people who previously had stable liver disease or never had liver problems.

You might also hear it called “fulminant hepatic failure” or “acute liver failure.” It can quickly become life-threatening. Call 911 right away if you or someone close to you shows any signs.

Your liver can fail if its cells get damaged and stop working. Fulminant hepatitis is most often caused by:

An overdose of acetaminophen. This painkiller is found in many over-the-counter and prescription medicines. Taking one very large dose can cause your liver to fail quickly. The same may happen if you take more than the recommended amount for several days in a row.

If you or someone you know has taken too much acetaminophen, call 911 right away.

Viral hepatitis. Infection from certain viruses, including hepatitis A, B, C, D, or E, may lead to sudden liver failure.

Some less common causes of fulminant hepatitis include:

  • Prescription medicines. Some antibiotics, cancer medicines, and other drugs can cause liver damage that leads to liver failure.
  • Certain viruses. Epstein-Barr virus, for example, or hepatitis A, B, or C, or herpes simplex virus may cause fulminant hepatitis.
  • Autoimmune hepatitis. This happens when your immune system attacks and damages liver cells.
  • Cancer. Tumors that start or spread to the liver can cause it to fail.
  • Clotting problems in the liver. One disease that affects the clotting in the vein that drains into the liver, is called Budd-Chiari syndrome. It causes blockages that can lead to liver failure.
  • Mushroom poisoning. The wild mushroom Amanita phalloides, also called the "death cap mushroom," is very dangerous to eat. It may seem safe to eat. But it has very strong toxins that damage the liver.
  • Wilson’s disease. This disorder allows copper to build up in your liver and other organs. Too much copper can be dangerous.
  • Some herbal products such as kava, ma huang (ephedra), and comfrey may lead to liver failure.

In many cases, doctors can’t find the cause of fulminant hepatitis.

At first, these may include:

If it gets worse, symptoms include:

  • Yellowing of your skin or eyes (jaundice)
  • Feeling very confused
  • Sleepiness
  • Changes in your personality or behavior, such as being more irritable or disoriented
  • Bleeding or bruising more easily
  • Stomach swelling

Your doctor will ask about your medical history, any past drug use, and if you’ve been exposed to toxins. They will also check for symptoms of hepatitis and test how mentally alert you are.

To help diagnose and find the cause of fulminant hepatitis, your doctor may ask for:

  • Blood and urine tests. Results can show how well your liver works. Your doctor will also do a test to see how long it takes for your blood to clot. When you have fulminant hepatitis, blood doesn’t clot as fast as it should.
  • Scans of your liver. Imaging tests allow your doctor to check the liver for damage, vein problems, tumors, or other issues. You may get an ultrasound, MRI, or CT scan.
  • A liver biopsy. Your doctor will remove a small piece of your liver tissue to check.

You will likely go into a hospital’s intensive care unit. Treatment for sudden liver failure depends on the cause. It may include any of the following.

Antidotes. This is a type of medicine used to counteract the effect of poison. If your liver suddenly starts to fail from an overdose of acetaminophen, your doctor may give you an antidote called N-acetylcysteine to stop the effects. This medicine may also help treat other causes of acute liver failure.

Other antidotes can help reverse the effects of mushroom poisoning and help reduce liver damage.

Medicines to treat hepatitis. Doctors use antiviral medicines to treat some forms of viral hepatitis. For example, if hepatitis B is the reason your liver is failing, an antiviral drug can fight the virus. Other antivirals may help if the herpes simplex virus is causing fulminant hepatitis.

You may get steroids if autoimmune hepatitis is the cause.

Liver transplant. If other treatments can’t get your liver to work again, you may need a new liver. If you get approved for a liver transplant, your name goes on a waiting list to get a donated organ. People with the most urgent need top the list.

During a liver transplant, a surgeon removes your damaged liver and replaces it with a healthy one from a donor.

Scientists are researching new treatments that could reduce or delay the need for a liver transplant.

Your doctor will also treat symptoms and side effects you have. That care may include:

  • Medicines to relieve pressure on your brain. One of the most serious side effects of acute liver failure is swelling in the brain. Extra fluid causes pressure to build up, which can lead to brain damage. Certain medicines can help ease the swelling.
  • Tests to check for infections. Fulminant hepatitis makes you more likely to get an infection in your blood or urinary tract, for example. Blood or urine tests can find the infection so your doctor can treat it.
  • Medicines to prevent bleeding. Your liver makes chemicals that help your blood clot. When your liver is failing, it can’t make enough of them. As a result, the chance of severe bleeding in your body is higher. Medicine can help prevent bleeding. If you do lose a lot of blood, you may need a blood transfusion.

In some cases, you can. The two most common causes of fulminant hepatitis are acetaminophen overdose and viral hepatitis. To help lower your chances:

  • Take acetaminophen as directed. Check the label for the recommended dose, and don’t take more than that.
  • Avoid contact with other people’s blood and body fluids. This can lower your chance of getting infected with a hepatitis virus. If you visit developing countries, you should avoid the local tap water. And there are vaccines available to prevent hepatitis A and hepatitis B, which are more common in some parts of the world. You can check the CDC’s website for traveler’s health to find out what vaccinations and other precautions you need to take in different countries.