You should not receive hepatitis B vaccine if you are allergic to yeast.
This vaccine will not protect against hepatitis B if you are already infected with the virus, even if you do not yet show symptoms.
Before taking this medicine
Hepatitis B vaccine will not protect against infection with hepatitis A, C, and E, or other viruses that affect the liver. It may also not protect against hepatitis B if you are already infected with the virus, even if you do not yet show symptoms.
You should not receive this vaccine if you have ever had a life-threatening allergic reaction to any vaccine containing hepatitis B, or if you are allergic to yeast.
If you have any of these other conditions, your vaccine may need to be postponed or not given at all:
multiple sclerosis;
kidney disease (or if you are on dialysis);
a bleeding or blood clotting disorder such as hemophilia or easy bruising;
weak immune system (caused by disease or by using certain medicine);
an allergy to latex; or
a neurologic disorder or disease affecting the brain (or if this was a reaction to a previous vaccine).
You can still receive a vaccine if you have a minor cold. If you have a more severe illness with a fever or any type of infection, your doctor may recommend waiting until you get better before you receive this vaccine.
It is not known whether this vaccine will harm an unborn baby. However, if you are at a high risk for infection with hepatitis B during pregnancy, your doctor should determine whether you need this vaccine.
If you are pregnant, your name may be listed on a pregnancy registry to track the effects of this vaccine on the baby.
It may not be safe to breastfeed while receiving  hepatitis B adult vaccine. Ask your doctor about any risk.
How is this vaccine given?
This vaccine is given as an injection (shot) into a muscle. A healthcare provider will give you this injection.
The hepatitis B vaccine is given in a series of 2 to 4 shots. The booster shots are sometimes given 1 month and 6 months after the first shot. If you have a high risk of hepatitis B infection, you may be given an additional booster 1 to 2 months after the third shot.
Your individual booster schedule may be different from these guidelines. Follow your doctor's instructions or the schedule recommended by the health department of the state you live in.
What happens if I miss a dose?
Contact your doctor if you will miss a booster dose or if you get behind schedule. The next dose should be given as soon as possible. There is no need to start over.
Be sure to receive all recommended doses of this vaccine or you may not be fully protected against disease.
What happens if I overdose?
An overdose of this vaccine is unlikely to occur.
