The chickenpox (varicella) vaccine often causes fevers and a mild chickenpox rash. Very rarely, vaccines against chickenpox can cause serious side effects like seizures or brain reactions. Children who are vaccinated can also develop shingles as adults.
Can the chickenpox vaccine cause shingles?
What are common chickenpox vaccine side effects?
What are severe chickenpox vaccine side effects?
Can I give my child aspirin?
What is Reye Syndrome?
Can the chickenpox vaccine cause birth defects?
Who has the highest risk of side effects?
When should I call a doctor?
What are less serious side effects?
What is in the chickenpox vaccine?
What other ingredients are in Varivax?
Does the chickenpox vaccine contain adjuvants?
Where can I get more information?
Serious side effects of the chickenpox vaccine are extremely rare. The reported injuries include severe allergic reactions, skin rashes, lung or liver infections, meningitis (brain inflammation), seizures, pneumonia, chickenpox infections from the virus in the vaccine, and more.
Yes. The chickenpox vaccine contains a live virus. Once you get vaccinated, the virus stays in your body forever. In about 33% of adults, the virus re-activates and causes a devastating skin rash called shingles.
One in five people who get shingles develop Post-Herpetic Neuralgia, a severe type of nerve damage that causes chronic pain. One explanation for the shingles epidemic in the U.S. is widespread chickenpox vaccination in children, but studies are inconclusive.
The most common chickenpox vaccine side effects in children ages 1-12 years old were fever over 102°F (14.7%) and injection-site complaints (19.3%) such as pain, soreness, swelling, rash, itching, or stiffness. The most common vaccine side effects in adults over 13 years old were injection-site complaints (24.4%) and fever over 100°F (24.4%). All ages commonly suffered mild chickenpox-like skin rashes (7%).
- Seizure (jerking or staring)
- Fever-induced seizure (febrile seizure)
- Brain reactions
- Anemia (low blood count)
- Anaphylaxis (allergic reaction)
- Necrotizing retinitis (eye disorder)
- Pregnancy complications
- Bleeding disorders
- Guillain-Barré Syndrome
- Stevens-Johnson Syndrome
- Erythema Multiforme
- Bell’s palsy
No. Fever is a common vaccine side effect, but do NOT not use aspirin for 6 weeks after the chickenpox vaccine due to Reye Syndrome, a vaccine side effect that can cause brain damage.
Reye’s Syndrome (Ryes) is a rare side effect that causes sudden brain damage, liver damage, mental changes, confusion, seizures, vomiting, tiredness, irritability, hearing loss, and other serious complications.
No one knows if the chickenpox vaccine causes birth defects, but pregnant women should NOT get vaccinated because wild-type varicella (natural chickenpox infections) are known to cause birth defects. Do not get pregnant for 3 months after receiving the vaccine.
Babies with congenital varicella syndrome may have low birth weight, skin problems, brain damage, seizures, intellectual disabilities, Horner’s syndrome, incontinence, or blindness.
Yes. About 7% of people get a mild chickenpox rash with a few bumps after receiving the vaccine. This rash is contagious, so you should avoid contact with non-immunized people for 6 weeks. In very rare cases, the chickenpox vaccine causes serious infections.
- Pregnant women who are not immune
- Newborn infants
- People with weak immune systems
- People on medications that suppress the immune system
Call 9-1-1 and get medical attention immediately if you have any of these symptoms:
- Severe skin rash
- Facial swelling (lips, tongue, throat)
- Cough, chest tightness, breathing problems
- Seizure (black-out or convulsions)
- Bruising or bleeding more easily than normal, red spots under the skin, severe paleness
- Behavior changes
- High fever within a few hours or weeks after the vaccine
- Vomiting, headache, stiff neck, sensitivity to light
- Redness or pain where the shot was given
- Low fever
- Mild skin rash
- Runny or stuffy nose
- Sore throat
- Tired feeling
- Sleep problems (insomnia)
- Joint or muscle pain
- Nausea, vomiting, stomach pain, diarrhea
Varivax contains a live varicella (chickenpox) virus that is “attenuated,” meaning it has been weakened, but it still causes a mild infection. The virus came from a child who was infected with a wild-type Oka strain.
This is a list of other chickenpox vaccine ingredients, as well as substances used in manufacturing that may remain at low levels:
- monosodium L-glutamate (MSG)
- sodium phosphate dibasic
- potassium phosphate monobasic
- potassium chloride
- sodium phosphate monobasic
- potassium chloride
- residual components of MRC-5 cells including DNA and protein
- fetal bovine serum
- human diploid cell cultures (WI-38)
- embryonic guinea pig cell cultures
- human embryonic lung cultures
No. An adjuvant is a mildly toxic vaccine ingredient that triggers a stronger immune response when a virus or bacteria is too weak to trigger immunity alone. There is controversy over side effects of some adjuvants (i.e., aluminum, formaldehyde, thimerosal, mercury, etc.), but the chickenpox vaccine has no added adjuvants.