Vaccine safety

What is normal after vaccination?

Some people may experience side effects, or adverse events, after getting a vaccine. Usually these are mild and go away on their own after 2–3 days. 

Babies and infants

After a baby or an infant gets a vaccine, they may experience some mild and temporary side effects:

  • slightly unsettled and cry a little more than usual 
  • tiredness for a day or two
  • mild diarrhoea or a few vomits after the oral Rotarix vaccine which sometimes may last up to a week. You can get more information about Rotarix vaccination here.
  • slightly red, itchy or sore legs or arm for a day or two
  • a small lump at the injection site. This may last for a few weeks. This usually does not require any treatment.
  • feel hot and have a temperature >38 degrees
  • a rash after MMR or chicken pox vaccine. This rash is not contagious.

Older children and adults

After an older child or an adult gets a vaccine, they may experience some mild and temporary side effects:

  • headache and tiredness for a day or two
  • slightly red, itchy or sore arm for a day or two
  • a small lump at the injection site. This may last for a few weeks. This usually does not require any treatment.

What you can do to help

Babies and infants

  • They may need to be cuddled and comforted more often. 
  • They may need more frequent breast feeds or drinks throughout the day.
  • They can be given a bath as normal.
  • If the injection site is red and warm to touch, you can put a cool wet cloth (not an ice pack) on their leg or arm.
  • If your baby feels hot, do not wrap them in too many blankets or clothes.

Although routine use of paracetamol or ibuprofen after immunisations is not recommended, if your baby has a fever (temperature over 38 degrees) or is in pain, you can give paracetamol or ibuprofen. Follow the directions on the bottle.

You can get more information about fever here.

Older children and adults

  • If allowed, they can have paracetamol or ibuprofen if their arm is sore. Follow the directions on the packaging.
  • If the injection site is red and warm to touch, you can put a cool wet cloth (not an ice pack) on their arm.
  • It really helps to keep moving the arm after an immunisation so they can still play sport that day.
  • It is ok to have a shower after an immunisation.
  • They should keep drinking plenty of oral fluids, preferably water.

When to see a doctor

You or your child need to see a doctor if:

  • paracetamol or ibuprofen is not relieving the fever, particularly for babies and infants 
  • your baby has sudden unusual screaming episodes with vomiting or blood in the bowel motion
  • your symptoms are not improving or getting worse.

COVID-19 vaccines

Like other vaccines, COVID-19 vaccines can also cause side effects. Usually these are mild and go away without treatment in 1–2 days. Currently two COVID-19 vaccines are being used in Australia: the Pfizer vaccine and the AsraZeneca vaccine. The most common side effects for both vaccines include:

  • pain at the injection site
  • tiredness
  • headache
  • muscle pain
  • chills
  • joint pain 
  • fever. 

Sometimes these flu-like side effects can mean that people struggle to carry out their usual activities for a day or so. It is important to adequately rest as needed after a COVID-19 vaccine. For more detailed information about the side effects of each vaccine, refer to:

After your COVID-19 vaccination (Comirnaty)

After your COVID-19 vaccination (COVID-19 Vaccine AstraZeneca) 

 

Related pages:

NCIRS COVID-19 vaccines: Frequently asked questions

COVID-19 vaccination program in Australia

Sharing Knowledge About Immunisation
 

Last updated April 2023
Vaccine safety