Comvax is a vaccine used to prevent hepatitis B and Hib (a type of bacteria that can cause life-threatening diseases). It is typically given as three doses, with the first dose given at two months of age. The vaccine works by "tricking" the body into thinking it has been exposed to Hib bacteria and hepatitis B. Possible side effects include irritability, fever, and drowsiness.
What Is Comvax?Comvax® (Hib vaccine and hepatitis B vaccine) is a childhood vaccine. It is a combined vaccine that provides protection against the following:
- Haemophilus influenzae type b (Hib), a type of bacteria that can cause potentially life-threatening diseases
- Hepatitis B.
(Click Comvax Uses for more information on what the medication is used for, including possible off-label uses.)
Thimerosal Content and Other Concerns
Comvax does not contain thimerosal (a mercury-containing preservative). Parents who are concerned about exposing their children to thimerosal can be confident that this vaccine has no thimerosal -- not even trace amounts.
Some parents also are concerned about the aluminum content of vaccines. Comvax contains 225 mcg (0.225 mg) of aluminum per dose.
This vaccine is not made from human fetal components or animal components, unlike some vaccines.
Who Makes Comvax?Comvax is made by Merck & Co., Inc.
How Does It Work?This vaccine contains hepatitis B surface antigens, which are proteins on the outer surface of the virus that can be recognized by the immune system. Unlike older versions of the hepatitis vaccine, currently available vaccines (including Comvax) are not made using human blood products. Instead, they are made using recombinant DNA technology. This vaccine is not "live," so there is absolutely no chance that a person could get hepatitis B from it.
This vaccine also contains Hib polysaccharides, which are sugar molecules from the outside coating of the Hib bacteria.
The components of this vaccine "trick" the body into thinking it has been exposed to Hib bacteria and hepatitis B virus, without the risk of being exposed to the actual bacteria or virus. The body produces antibodies that will help fight infection if future exposure occurs.