What to do if you think you or your child has had a severe reaction to a vaccine

One of the most serious problems that can occur with getting any vaccine is a severe allergic reaction. If this were to happen, it would most likely happen within a few minutes to a couple of hours after getting a vaccine. Even though this is rare, it’s important to seek medical help if this occurs.

  • Signs of a severe allergic reaction:
    • Hives
    • Swelling of the face and/or throat
    • Difficulty breathing, wheezing and/or hoarseness
    • Rapid heartbeat
    • Dizziness
    • Weakness
    • Paleness

Other indicators that your child may have had a serious reaction to a vaccine:

  • Very high fever
  • Behavioral changes

*Note: brief fainting spells are not uncommon following a vaccination. This does not usually indicate a serious reaction to the vaccine. However, fainting spells can lead to injury. Inform the doctor if your child feels dizzy or light-headed, or has vision changes or ringing in the ears. Laying down immediately following vaccination can prevent this from happening again.

What to do if you or your child has a serious reaction to a vaccine:

  • If the reaction is severe call 9-1-1 or get the person to the nearest hospital. Otherwise, call your doctor.
  • Report the reaction to the “Vaccine Adverse Event Reporting System” (VAERS). Your doctor might file this report, or you can do 
it yourself through the VAERS web site, or by calling 1-800-822-7967. VAERS is only for reporting reactions. They do not give medical advice.
  • Of course, do not give your child the follow-up boosters for the vaccine he has had a reaction to. And speak with your child’s doctor about your vaccination options.

Other important links:

  • The National Vaccine Injury Compensation Program (VICP)–a federal program created to compensate people who may have been injured by certain vaccines. To learn about the program and about filing a claim, you may call 1-800-338-2382 or visit the VICP website.
  • Contact the Centers for Disease Control and Prevention (CDC) by calling 1-800-232-4636 or visit
ing the CDC’s vaccine website.
  • Call or click your local or state health department.
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