An allergic reaction to the varicella vaccine is not something that happens to many people. However, those who are allergic to pollen or egg are at greater risk. Reactions to the vaccine usually occur more often after the first dose than the second.
Vaccination against the varicella-zoster virus, which produces chickenpox, is much safer than getting the disease.
Centers for Disease Control and Prevention
Risk Factors for an Allergic Reaction
Fortunately, severe allergic reactions are rare, only one or two per 1 million vaccines, according to experts at the Johns Hopkins Children's Center. The public health authorities of the Centers for Disease Control and Prevention say that being vaccinated against the varicella-zoster virus is much safer than getting chickenpox.
If you already have an allergy, such as hay fever, your chances of having an allergic reaction to a medicine or vaccine are slightly greater than if you had no history. If you have had a mild allergic reaction to the vaccine in the past, subsequent exposures may produce a more serious reaction. A history of asthma, heart disease, and hypertension may also increase your risk of a serious reaction to a medication or vaccine.
Allergy to vaccines
In some rare cases, the active component of the vaccine (an attenuated form of the varicella virus) can produce a reaction. However, allergic reactions to other components of the vaccine can sometimes be detected. The candidates are neomycin and egg, since the virus is cultured in chicken embryos before being inactive. Doctors at Children's Hospital of Philadelphia warn that the vaccine may also contain gelatin, which causes allergic reactions in some people.
An allergic reaction to the vaccine could cause:
• Urticaria • Skin rash • Itching • Fever
Anaphylaxis, a rare but life-threatening allergic reaction, can produce:
• Missing of breath • Wheezing • Hypotension • Tachycardia • Swelling of the face, tongue, throat or lips • Dizziness, confusion or unconsciousness • Vomiting • Diarrhea
This severe allergic reaction requires immediate medical attention to prevent coma or death.
Even if the child has had a previous allergic reaction to the vaccine, it is possible to vaccinate in the future. One way is to use a vaccine that does not contain the material that caused the first reaction, if it could be identified.
Johns Hopkins pediatricians claim that some children with a history of allergies to vaccines can be vaccinated even if an allergen-free vaccine is not available. This approach requires that vaccination be followed by rigorous medical supervision in the hours that follow.
About the author
Dr. Boyan Hadjiev has practiced medicine for five years. He has a double certification in Internal Medicine (2003) and in Allergy and Immunology (2005).
Dr. Hadjiev graduated from the University of Michigan with a degree in Biology and earned a Medical degree from the Cleveland Clinic-Case Western Reserve School of Medicine.