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Twinrix (hepatitis A and B vaccine)

Main useActive ingredientManufacturer
Prevention of hepatitis A and B Inactivated hepatitis A virus and hepatitis B surface antigenGlaxoSmithKline

How does it work?

Twinrix is a combination vaccine against hepatitis A and hepatitis B. It contains inactivated hepatitis A virus and an inactivated extract of the hepatitis B virus. The vaccine works by provoking the body's immune response to these viruses, without causing the diseases.





Twinrix stimulates the immune system to produce antibodies against the hepatitis A and B viruses. It is given to prevent hepatitis A and B.

Hepatitis A and B are not given as routine vaccinations. They are only given to people who are at high risk of contracting hepatitis A or B, for example health care workers who have direct contact with blood and travellers to high risk areas.

This vaccine is given as a course of three injections; the second dose one month after the first, followed by a third dose after a further six months. The injections are administered into the muscle of the upper arm in adults, adolescents and older children, and the thigh in infants.

In exceptional circumstances in adults, for example if travel departure is within a month after starting the vaccination course and there is not enough time for the standard 0, 1, 6 month schedule to be completed, a quicker schedule of three injections at 0, 7 and 21 days may be used. If you are given this faster course, it is recommended that you then have a fourth dose 12 months after your first dose of the vaccine.

Some vaccines remain effective for a lifetime, while others have to be updated after a few years. This vaccine provides immunity against hepatitis A for 10 years and hepatitis B for 5 years. A 'booster' injection can be given 5 years after the first course to provide continued immunity against both viruses. Alternatively, booster vaccines can be given separately; hepatitis B after 5 years and hepatitis A after 10 years.

What is it used for?

Twinrix adult is suitable for adults aged 16 years and over.

Twinrix paediatric is suitable for children and adolescents aged 1 to 15 years.



Not to be used in

  • People allergic to the antibiotic neomycin.



Use with caution in


In both these cases an injection into a muscle could cause bleeding and, for this reason, this vaccine may be administered under the skin (subcutaneously) instead. However, the vaccine may be less effective when administered this way.

Pregnancy and breastfeeding


  • The safety of giving this vaccine to women who are pregnant or breastfeeding has not been specifically studied. However, since it contains inactivated virus it is not expected to be harmful. It should be used with caution, and only if the expected benefit to the mother outweighs any potential risk to the infant. The manufacturer recommends that the vaccine course is delayed until after delivery, unless there is an urgent need to protect the mother against hepatitis B. Ask your doctor for advice before having this vaccine if you are, or think you might be pregnant, or you are breastfeeding.

Side effects


This vaccine contains no live virus and so cannot cause hepatitis A or B.

Very common (affect more than 1 in 10 people)

  • Pain and redness at the injection site.
  • Fatigue and headache in adults.


  • Swelling, itching or bruising at the injection site.
  • Feeling generally unwell (malaise).
  • Upset stomach or feeling sick.
  • Diarrhoea in adults.
  • Fatigue or drowsiness in children.
  • Irritability in children.
  • Headache in children.
  • Loss of appetite in children.


  • Aching muscles.
  • Vomiting.
  • Abdominal pain.
  • Upper respiratory tract infection.
  • Diarrhoea in children.
  • Rash in children.
  • Dizziness in adults.


  • Aching joints.
  • Swollen lymph glands.
  • Pins and needles or numb sensations.
  • Low blood pressure (hypotension).
  • Flu-like symptoms.
  • Chills.
  • Itching.
  • Rash in adults.
  • Decreased appetite in adults.
  • Dizziness in children.



How can this vaccine affect other medicines?

This vaccine is not known to affect other medicines.


In adults, this vaccine may be given at the same time as other vaccines, but if so, the other vaccines should be administered into separate sites and preferably into separate limbs. In children, the manufacturer recommends that this vaccine is given at different times to other vaccines.

Other hepatitis A and B vaccines

Ambirix is another brand of combination hepatitis A and B vaccine.

Avaxim, Epaxal, Havrix junior monodose, Havrix monodose and Vaqta paediatric are all hepatitis A vaccines.

Engerix B, Fendrix and HBvaxPRO are all hepatitis B vaccines.

Last updated 21.05.2009