Drug information

What is Twinrix?What is Twinrix?

What is Twinrix?

Twinrix is a vaccine approved by the U.S. Food and Drug Administration (FDA) to prevent hepatitis A virus infection (HAV) and hepatitis B virus infection (HBV) in adults 18 years of age and older.

HBV can be an opportunistic infection (OI) of HIV. An OI is an infection that occurs more frequently or is more severe in people with weakened immune systems—such as people with HIV—than in people with healthy immune systems. To learn more about OIs, read the HIVinfo What is an Opportunistic Infection? fact sheet. To learn how HIV and HBV are connected, read the HIVinfo HIV and Hepatitis B fact sheet.

The Guidelines for the Prevention and Treatment of Opportunistic Infections in Adults and Adolescents With HIV include recommendations on the use of Twinrix in people with HIV.

What should I tell my health care provider before receiving Twinrix?What should I tell my health care provider before receiving Twinrix?

What should I tell my health care provider before receiving Twinrix?

Before receiving Twinrix, tell your health care provider:

  • If you are allergic to yeast, neomycin, or any other ingredients in Twinrix; latex; or any medicines. Tell your health care provider if you have ever had any reactions to a previous dose of the vaccine or to any HAV or HBV vaccines.
  • About any medical conditions you have or have had, including:
    • Any diseases that may weaken your immune system
    • Any acute (sudden) illness with fever
    • History of fainting while receiving a vaccination
  • About any health conditions that may prevent you from receiving medicine by injection.
  • If you are pregnant or plan to become pregnant. Talk to your health care provider about the risks and benefits of receiving Twinrix during pregnancy.
  • If you are breastfeeding or plan to breastfeed. For mothers with HIV in the United States, the Guideline recommends speaking with your health care provider to discuss options for feeding your baby. Mothers with suppressed viral load have a less than 1% chance of transmitting HIV to their baby via their own milk. Although most medicines are safe to use while breastfeeding, some medicines should be avoided. Always let your health care provider know about all the medicines and supplements you are using before you start breastfeeding.
  • About other prescription and nonprescription medicines, vitamins, nutritional supplements, and herbal products you are taking or plan to take. Twinrix may affect the way other medicines or products work, and other medicines or products may affect how Twinrix works. Ask your health care provider if there are interactions between Twinrix and the medicines you take.

How is Twinrix given?How is Twinrix given?

How is Twinrix given?

A health care provider gives the Twinrix vaccine. The vaccine is injected into a muscle in the arm. In adults with HIV, vaccination with Twinrix is usually given as a series of either three or four vaccine shots over a 6- or 12-month period. Read any printed information that your health care provider gives you about Twinrix.

What side effects can Twinrix cause?What side effects can Twinrix cause?

What side effects can Twinrix cause?

Twinrix may cause side effects that can be mild or serious. To learn about possible side effects of Twinrix, see the FDA drug label or talk to your health care provider or pharmacist. Tell your health care professional if you have any side effect that bothers you or that does not go away. Your health care professional may be able to tell you about ways to prevent or reduce some side effects.

You may report vaccine side effects using the Vaccine Adverse Event Reporting System online.

Where can I find more information about Twinrix? Where can I find more information about Twinrix?

Where can I find more information about Twinrix?

Last Reviewed: March 13, 2025