Safety and first aid

Vaccination safety

Vaccination refers to the act of giving a vaccine to a person. A vaccine is the material used to immunise people against diseases.

Like any other medication, vaccines can have side effects. Side effects after vaccination are usually mild and short-lasting and do not need special treatment.

If the side effects seem severe or persistent, for example an ongoing high fever, breathing difficulties or convulsions seek medical advice.

Common side effects

Common side effects after a vaccination can include:

  • soreness, redness, or pain at the injection site
  • a small hard lump appearing at the injection site
  • fainting (mainly in teenagers and adults)
  • fever
  • vomiting
  • diarrhoea
  • decreased appetite
  • sleepiness
  • irritability.
Managing common side effects

Pain relief

The routine use of paracetamol at the time of vaccination is no longer recommended as today’s vaccines have fewer side effects.

You can use paracetamol to help with pain and fever after a vaccination, remembering to carefully follow the instructions on the packet.

Never give aspirin to a child or adolescent under 16. It can cause a rare, but severe illness called Reye’s Syndrome.

You can ease the soreness at the injection site by placing a wet cloth over it


This is mainly seen in adolescents and adults. If you feel light-headed or dizzy before or after a vaccination you should lie down until you feel better.

Vomiting and diarrhoea

See your doctor if these symptoms are severe or persistent.

Irritability, loss of appetite, sleepiness

These are common symptoms and do not require any treatment. These symptoms usually disappear after 24 to 48 hours – if they don’t, see your doctor.

Your child may need extra comforting after vaccination.


If you develop a fever higher than 38.5 °C after a vaccination take paracetamol (not aspirin) as directed depending on your weight and age. Make sure you drink extra fluids and wear light-weight, loose clothing.

If your child has a fever:

  • take their temperature regularly. If your child has a persistent high temperature, see your doctor.
  • give them extra fluids (for example more breast feeds or more water)
  • dress them in light clothing
  • do not give them a bath in cool water. This can cause shivering, which can increase the body’s core temperature.

Paracetamol may be taken if there is fever and pain – carefully follow the instructions on the pack.


Seizures (convulsions or fit) can occur in young children if they experience a fever after a vaccination. They usually last 20 seconds, rarely more than 2 minutes.

If you or your child has a seizure after a vaccination you should call an ambulance. You should always make sure your child sees a doctor if they have a seizure. There is usually no long-term damage from seizures in young children, but they should be checked by your doctor.

Rare reactions

Any medication, including vaccines, may have potentially serious side effects including a severe allergic reaction, such as anaphylaxis.

The risk of developing severe reactions after receiving a vaccine is extremely rare.

Your doctor or nurse is trained to recognise and manage any immediate, severe reactions.

A severe, anaphylactic reaction will generally occur within the first 15 minutes after receiving a vaccine, so it is important for you to wait at the place you have received your vaccination so that you can be observed for any reaction.

Surveillance for adverse events following immunisation

An adverse event following immunisation (AEFI) is an unwanted or unexpected event occurring after a vaccine has been given.

Such an event may be caused by the vaccine or may occur by chance after vaccination (that is, it would have occurred regardless of vaccination).

Vaccines can cause minor adverse events such as low-grade fever, pain or redness at the injection site, these symptoms are short lived.

Surveillance of AEFI is an integral part of a national vaccination program. Under the Health (Notification of Adverse Event After Immunisation) Regulations 1995, all WA medical officers are required to report any adverse events of concern to the Department of Health, providing a full description of the reaction to the vaccine.

This enables WA Health to identify new and unexpected AEFI and respond accordingly.

Reporting an adverse event

Not all side effects need to be reported such as, soreness or redness at the injection site or a slight fever that lasts less than a day. Read more aboutcommon minor side effects to vaccines that do not require reporting (PDF 43KB) (external site).

If you experience a significant AEFI you should tell your doctor what happened, the date and time it happened, and when you had the vaccination.

If your doctor is not available call healthdirect Australia on 1800 022 222. This service is available 24 hours a day, 7 days a week. A registered nurse will provide free advice about your health issues and concerns.

You can also report the reaction yourself using Western Australian Vaccine Safety Surveillance System (WAVSS) online (external site) or by calling the Central Immunisation Clinic on telephone 9321 1312, Monday to Friday, 8.30 am to 4.30 pm.

Find out more about adverse events and reporting them.

Vaccine Safety Net

The World Health Organization (WHO) has compiled a network of websites across the world that provide reliable information about vaccine safety. Visit Vaccine Safety Net (external site) to access global websites that have been evaluated by WHO as providing accurate, reliable information.

Australia’s Immunise Australia (external site), National Centre for Immunisation Research (external site) and Northern Rivers Vaccination Supporters (external site) are among those in the network.

Where to get help

  • See your doctor
  • Visit a GP after hours
  • Phone healthdirect on 1800 022 222
  • Phone the Immunise Australia Hotline on 1800 671 811


Public Health

This publication is provided for education and information purposes only. It is not a substitute for professional medical care. Information about a therapy, service, product or treatment does not imply endorsement and is not intended to replace advice from your healthcare professional. Readers should note that over time currency and completeness of the information may change. All users should seek advice from a qualified healthcare professional for a diagnosis and answers to their medical questions.

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