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Hepatitis B Vaccine


Margot L. Savoy

, MD, MPH, Lewis Katz School of Medicine at Temple University

Last full review/revision Jun 2021| Content last modified Jun 2021

The hepatitis B vaccine helps protect against hepatitis B and its complications (chronic hepatitis, cirrhosis, and liver cancer).

Generally, hepatitis B is more serious than hepatitis A and is occasionally fatal. Symptoms can be mild or severe. They include decreased appetite, nausea, and fatigue. In 5 to 10% of people, hepatitis B becomes chronic and can lead to cirrhosis and liver cancer.

For more information, see the Centers for Disease Control and Prevention's (CDC) Hepatitis B vaccine information statement.

(See also Overview of Immunization.)

Administration of Hepatitis B Vaccine

The hepatitis B vaccine is typically given in a series of two or three injections into a muscle. However, if people who have been vaccinated are exposed to the virus, a doctor measures their antibody levels against hepatitis B. If the antibody levels are low, they may need another injection of hepatitis B vaccine.

As a part of routine childhood vaccination, all children are typically given three doses: at birth, at age 1 to 2 months, and at 6 to 18 months. Infants who did not receive a dose at birth should begin the series as soon as possible.

The hepatitis B vaccine also is recommended for older children and adolescents who were not previously vaccinated. The vaccine can be given to any unvaccinated adult who wants to be protected from hepatitis B.

The vaccine is also recommended for all unvaccinated adults who are at increased risk of getting hepatitis B, such as the following:

  • People who work in professions where they may be exposed to blood or other potentially infectious body fluids, such as health care, custodial, or public safety workers
  • People who travel to areas where the infection is common
  • People with a chronic liver disorder (such as hepatitis C, cirrhosis, fatty liver disease, alcohol-related liver disease, and autoimmune hepatitis) or high levels of certain liver enzymes in their blood
  • People with kidney failure, including those who need dialysis
  • People who inject illegal drugs
  • People who have several sex partners
  • People who need to be evaluated or treated for a sexually transmitted disease
  • Men who have sex with men
  • Sex partners and household contacts of people known to be carriers of hepatitis B
  • People with HIV infection
  • People who are under age 60 and have diabetes and sometimes people who are age 60 and older who have diabetes
  • People who are employed by or are given care in places where there are people at high risk of hepatitis B (such as places where people with sexually transmitted diseases are treated and places where drug-abuse treatment and prevention services, services for injection drug users, and services for men who have sex with men are provided; hemodialysis centers, institutions for developmentally disabled people, correctional facilities, and HIV testing and treatment facilities)
  • Pregnant women if they are at risk of getting the infection or of getting very sick or dying of infection during pregnancy

If people have a temporary illness, doctors usually wait to give the vaccine until the illness resolves (see also CDC: Who Should NOT Get Vaccinated With These Vaccines?).

Side Effects of Hepatitis B Vaccine

Occasionally, the injection site becomes sore, and a mild fever develops.

People with a history of severe allergic reaction to baker’s yeast, which is used in the production of the hepatitis B vaccine, should not be given the vaccine.

More Information

The following are some English-language resources that may be useful. Please note that THE MANUAL is not responsible for the content of these resources.

  • Centers for Disease Control and Prevention (CDC): Information statement about hepatitis B vaccine
  • CDC: Information about people who should NOT get vaccinated with hepatitis B vaccine

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