Examples
|
| Twinrix | Havrix and Engerix-B | |
How It Works
Twinrix is a vaccine that provides active
immunity against both the
hepatitis A and
hepatitis B viruses. It is given in a series of 3
injections on the same schedule as the hepatitis B vaccine: an initial dose
followed by doses at 1 month and 6 months.
Why It Is Used
The vaccine can prevent infection with
one series of injections rather than two series. The U.S. Food and Drug
Administration (FDA) has approved its use only for people age 18 or older who
are at risk of infection with the hepatitis A virus (HAV) and the hepatitis B
virus (HBV). These include people who:
- Will travel to areas with moderate to high
rates of HAV and HBV. These include Africa, the Caribbean, Central America,
South America, Mexico, South and Southeast Asia, the Middle East, Eastern
Europe, Southern Europe, and the former Soviet Union.1
- Have long-term (chronic) liver disease.
- Use illegal
injectable drugs.
- Have anal contact with a sex
partner.
- Work in occupations that expose them to viruses, such as
some lab workers, people who provide emergency medical assistance, and day care
providers.
- Have clotting factor disorders and receive blood products.
How Well It Works
In clinical trials, 1 month after the
last dose, 100% of people were immune to hepatitis A, while 99.7% were immune
to hepatitis B.2 But in practice, immunity may not
approach these levels. Hepatitis B vaccine usually does not provide immunity
for more than 95% to 97% of people.
Immunity to the hepatitis B
virus is thought to be lifelong. The hepatitis A vaccine is effective for at
least 10 years.2
Side Effects
In trials of the vaccine, no serious side
effects occurred. The most common side effects were those that occur with the
individual hepatitis A and B vaccines, such as:
- Soreness at the injection
site.
- Headache.
- Fatigue.
See Drug Reference for a full list of side effects. (Drug
Reference is not available in all systems.)
What To Think About
Twinrix should not be given to
people who are allergic to the contents of the vaccine.
The
vaccine has not been tested in pregnant or breast-feeding women, so its safety
for these women and their babies is unknown.
To be most effective
before travel, two doses need to be given before departure. If only one dose
can be given, consider having the individual hepatitis A vaccine instead of one
shot of combination vaccine. It may provide better protection against hepatitis
A.2
Complete the new medication information form (PDF)
(What is a PDF document?)
to help you understand this medication.
References
Citations
Centers for Disease Control and Prevention (2008).
Yellow Book: Health Information for International Travel 2008. Available online:
http://wwwn.cdc.gov/travel/contentYellowBook.aspx.
Twinrix: A combination hepatitis A and B vaccine
(2001). Medical Letter on Drugs and Therapeutics,
43(1110): 67-68.
Credits
| Author | Maria G. Essig, MS, ELS |
| Editor | Susan Van Houten, RN, BSN, MBA |
| Associate Editor | Pat Truman, MATC |
| Primary Medical Reviewer | Kathleen Romito, MD - Family Medicine |
| Specialist Medical Reviewer | W. Thomas London, MD - Hepatology |
| Last Updated | September 9, 2008 |
Centers for Disease Control and Prevention (2008).
Yellow Book: Health Information for International Travel 2008. Available online:
http://wwwn.cdc.gov/travel/contentYellowBook.aspx.
Twinrix: A combination hepatitis A and B vaccine
(2001). Medical Letter on Drugs and Therapeutics,
43(1110): 67-68.