Vaccine side effects and safety

All medicines, including vaccines, are continually monitored for safety and potential side effects.

The chance that a vaccine will cause you or your child serious harm is extremely small and being vaccinated is less harmful than the alternative of getting the disease.

You (or your child) should have all the recommended vaccines at the recommended times, unless your health professional advises you not to have them for medical reasons. For example, if you have a weakened immune system due to another infection or medicines that you are taking to suppress your immune system.

Before your child has any vaccination, always let your doctor know if they have any allergies, or has had any reactions to a vaccine in the past. This is because very rarely, some people may be allergic to some part of a vaccine. For example, to the very tiny amounts of egg protein in the flu vaccine, or an antibiotic that can sometimes be used in the vaccine making process.

Even though there are only tiny amounts of the substance in the vaccine, if someone with the allergy has the vaccination, they may have a severe reaction called anaphylaxis. Anaphylaxis is extremely rare but can be life-threatening and always needs urgent medical treatment. Fewer than one in a million people will have anaphylaxis after a vaccination.

If you have had a reaction to a vaccination in the past, tell your doctor. They will let you know if it is recommended for you to receive a particular vaccine. Occasionally, your doctor may refer you to a special immunisation clinic where you will be assessed and very closely monitored after you have been vaccinated.

What are the side effects of vaccines?

Most of the side effects associated with vaccines are minor, and usually go away within a few days.
The most common* side effects of almost all vaccines are:

  • fever (a temperature higher than 38.5°C)
  • redness, swelling and tenderness at the injection site
  • headache, tiredness and nausea.

Vomiting, diarrhoea, and muscle or joint pain, occur less frequently.

Read more about the side effects of vaccines available in Australia and what to do if your child has a fever after a vaccination.

*Common: 1 to 10 in every 100 people will experience these side effects.

Who can I ask about side effects?

If you’re concerned that you or your child may have had side effects related to a vaccine, seek medical advice. To report and discuss possible side effects, call the Adverse Medicines Events (AME) Line on 1300 134 237 from anywhere in Australia (Monday–Friday, 9am–5pm AEST).