Everything You Need to Know About Hepatitis B

Medically Reviewed By Youssef (Joe) Soliman, MD
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Hepatitis B is a serious infection that affects the liver. It most often spreads through contact with blood or other bodily fluids. This article defines hepatitis B. It also discusses the symptoms, causes, and treatments associated with the condition.

Sex and gender disclaimer

Sex and gender exist on spectrums. This article uses the terms “female” and “male” to refer to sex that was assigned at birth. 

Learn more about the difference between sex and gender here.

What is hepatitis B?

Female lying in bed
Eddie Pearson/Stocksy United

Hepatitis B is a serious viral liver infection due to the hepatitis B virus. The term “hepatitis” means inflammation of the liver. It is a form of liver disease.

The hepatitis B virus infects the liver, which causes harmful inflammation and impairs liver function. The liver is an essential organ required for hundreds of functions. These include removing waste products from the blood, controlling cholesterol production, and making clotting factors, immune substances, and bile.

Hepatitis B most commonly spreads from the birthing parent to the child during the birth process. Other ways it spreads include:

  • having sex without a condom or another barrier method with someone who has the virus
  • sharing needles, syringes, or drug preparation equipment
  • sharing items such as toothbrushes, razors, and medical equipment with someone who has the virus
  • coming into direct contact with the blood or open sores of someone who has the virus
  • having exposure to the blood of someone who has the virus through a needlestick or another sharp instrument

Hepatitis B passes from person to person in blood, semen, and other bodily fluids. It cannot spread through casual contact, such as hugging or shaking hands.

It starts as an acute infection that may or may not cause symptoms in adults. Around 90% of healthy adults will clear the virus and fully recover from the acute phase. Some will go on to develop a chronic infection. However, around 90% of infants who contract hepatitis B during birth will develop a chronic infection.

After exposure to the virus, it can take around 90 days to develop symptoms. Approximately two-thirds of people with the virus do not have symptoms. People rarely know that they have hepatitis B.

However, you can pass the virus to others even if you do not have symptoms.

Hepatitis B can become life threatening if it develops into a chronic condition. However, it is highly preventable with the safe and effective vaccine.

Read about what your liver does here.

What are the symptoms of hepatitis B?

Symptoms of acute hepatitis B occur in up to half of adults and children older than 5 years who have the virus. Symptoms typically appear within 90 days of exposure to the virus, but they can begin any time between 8 weeks and 5 months after the initial exposure.

Symptoms also generally last for several weeks, but some people feel sick for up to 6 months. Most people recover from this acute infection.

Children younger than 5 years and immunosuppressed adults tend not to show symptoms of hepatitis B infection.

The symptoms of hepatitis B include:

An acute hepatitis B infection can progress to a chronic infection. Similar to acute hepatitis B, some people have symptoms of chronic hepatitis B, but most do not.

In some cases, people do not realize that they have a chronic infection until they develop signs and symptoms of liver disease and liver failure.

If you experience symptoms of hepatitis B or believe that you may have had exposure to the virus, contact a doctor.

What are the risk factors for hepatitis B?

Anyone can get hepatitis B. However, some people are more at risk of getting the virus than others.

People at greater risk of contracting hepatitis B include

  • infants born to birthing parents who have the virus
  • healthcare professionals who have exposure to blood at work
  • males who have sex with males
  • people who share needles for injectable drugs
  • people who have other sexually transmitted infections (STI)
  • people who have sex with someone who has the virus without using a condom or another barrier method
  • people who live with someone who has the virus

Reducing your risk of hepatitis B

Hepatitis B infection is preventable.

You can lower your risk of contracting hepatitis B by:

  • getting the hepatitis B vaccine
  • using a condom or another barrier method during sex
  • not sharing needles
  • knowing the STI and hepatitis B status of any sexual partners
  • researching tattoo and piercing shops to make sure they use sterile equipment
  • wearing gloves when administering first aid or cleaning up or coming into contact with blood

Seek immediate medical care if you may have had exposure to hepatitis B.

Treating the exposure within 24 hours may prevent infection. Postexposure treatment includes the vaccine and possibly hepatitis B immune globulin (HBIG). HBIG contains antibodies against hepatitis B.

What are the treatments for hepatitis B?

If you have symptoms of hepatitis B infection and seek medical attention, your doctor will typically check your liver function with blood tests.

Acute hepatitis B is not generally treated with medications. If you have mild symptoms, your doctor will usually recommend the following:

  • getting plenty of rest
  • eating well
  • drinking plenty of fluids

If your symptoms become severe, you may require hospitalization for treatment.

If hepatitis B becomes chronic, you may need to start treatment right away. In general, treatment is most effective when there are signs of active liver disease. Your doctor may monitor your liver to decide when it is the best time for you to start treatment.

Not everyone with chronic hepatitis B requires treatment.

Chronic hepatitis B treatment includes two categories of medications.

The first category is antiviral medications. These drugs slow or stop viral reproduction, which helps prevent liver damage. Antivirals will not cure hepatitis B, and they will only work for as long as you are taking them. Because of this, you typically need to take these medications for life.

First-line antiviral medications for hepatitis B include:

  • entecavir (Baraclude)
  • tenofovir alafenamide (Vemlidy)
  • tenofovir disoproxil (Viread)

Second-line antiviral medications for hepatitis B include:

  • adefovir dipivoxil (Hepsera)
  • lamivudine (Epivir-HBV, Heptodin, Zeffix)
  • telbivudine (Sebivo, Tyzeka)

The other type of hepatitis B medication is interferon. Interferons are immune stimulators that help your body fight infection.

Interferon drugs for hepatitis B include:

  • Pegylated interferon (Pegasys): This is a weekly injection and a first-line treatment.
  • Interferon-alpha (Intron A): This is an older product that is no longer a preferred treatment.

Interferons are sometimes difficult to take due to side effects. They are generally not the first choice for hepatitis B treatment. They are typically useful when people are not ready for long-term treatment.

What are the potential complications of hepatitis B?

Chronic hepatitis B can lead to serious complications. Ongoing inflammation in the liver can cause cirrhosis, which is scarring in the liver. This condition prevents the liver from functioning normally.

If the damage continues, end stage liver disease and liver failure can occur. A liver transplant is the only effective treatment for liver failure.

Another possible complication of chronic hepatitis B is that it puts you at risk of developing hepatitis D. Hepatitis D can only develop in someone with hepatitis B, and it can cause any symptoms and liver disease to get worse.

View some frequently asked questions about liver disease here.

Other frequently asked questions

Here are some more questions that people have asked about hepatitis B. Dr. Youssef Soliman, M.D., has answered these questions.

What is the difference between hepatitis B and C?

Hepatitis C is another virus that affects the liver. It is an RNA virus that is more commonly transmitted through different forms of contact with blood, such as when sharing needles, razors, or other personal items with people who have hepatitis C. Another major difference is that hepatitis C is curable with direct-acting antiviral drugs.

What is worse, hepatitis B or C?

Both viruses have the potential to cause lasting liver disease, including liver cancer. With hepatitis B, the risk of developing liver cancer remains regardless of whether or not a person has cirrhosis. With hepatitis C, cirrhosis almost always has to develop before the risk of cancer increases.

How often do you need the hepatitis B vaccine?

It depends on age, special health conditions, and vaccination availability. The Centers for Disease Control and Prevention (CDC) recommends routine vaccination in adults ages 19–59 years with a two, three, or four dose series.

Is the hepatitis virus a sexually transmitted infection?

Yes. Hepatitis B has the highest risk of being sexually transmitted. People at particular risk include those who have multiple sexual partners, those who engage in sexual activities with people who have the virus without using barrier protection, and males who have sex with males.


Hepatitis B is a serious infection of the liver that results from exposure to the hepatitis B virus.

Many people with hepatitis B do not experience any symptoms. However, it is still possible to spread the virus to others.

Hepatitis B is preventable, most commonly with the vaccine.

If you are experiencing symptoms of hepatitis B or believe that you may have had exposure to the virus, contact your doctor.

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Medical Reviewer: Youssef (Joe) Soliman, MD
Last Review Date: 2022 May 27
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