- Fever is a part of your body’s immune response and is usually caused by infection.
- A fever causes a high temperature but can also cause sweating and chills.
- You can take your temperature with a thermometer to check if you have a fever.
- If you or your child has a fever, rest, keep cool and stay hydrated.
- If you experience other symptoms like severe headache, vomiting, confusion or a stiff neck, see a doctor.
What is a fever?
A fever is when your body temperature is higher than normal. Having a fever can also be called ‘having a temperature’.
A normal temperature is around 36°C to 37°C, although it depends on:
- your age
- what you’ve been doing
- the time of day
- how you take the measurement
What are the symptoms of a fever?
If you have a fever, you will have a high temperature. A high temperature is usually considered to be above 38°C. You may also have other symptoms, such as:
- aching muscles and joints
What causes a fever?
Fever is a part of your immune system response. If you have a fever, it is a sign that your body is working hard to get well.
A high temperature is most often caused by a viral infection such as:
However, fever can also be caused by bacterial infections, such as:
CHECK YOUR SYMPTOMS — Use the Symptom Checker and find out if you need to seek medical help.
How is fever diagnosed?
Fever is diagnosed by taking your temperature. You can do this yourself. You probably have a fever if your temperature is 38°C or higher.
A doctor can find the cause of your fever by:
- asking questions about your symptoms
- examining you
- perhaps doing some blood tests
Taking your temperature
You can take your temperature quickly and easily using a thermometer.
You can buy a thermometer from a chemist or supermarket. Different types of thermometers measure temperature through different parts of your body, such as:
- touchless forehead thermometers
- in the ear
- under the armpit
- under the tongue
- in the rectum
Make sure the thermometer is clean.
Check the manufacturer's instructions to find out how to use your thermometer.
Digital thermometers can measure temperature faster than a glass thermometer.
Ear thermometers can be used to measure the temperature of children over 6 months.
Plastic tape thermometers, which you hold on your forehead, aren’t an accurate way of taking your temperature.
Mercury thermometers were used in the past. You shouldn’t use mercury thermometers today. They can break, releasing small shards of glass and mercury fumes.
If you break a mercury thermometer, there are steps you can take to stay safe.
- Get any people or animals out of the room.
- Clean the spill using gloves.
- Pick up any broken glass with paper towel.
- Scrape up any mercury using cardboard.
- Place waste into zip lock bags or a sealable container.
- Keep the waste stored until you can take it to a household hazardous waste disposal facility.
- Call the Poisons Information Centre on 13 11 26 if anyone is exposed to mercury.
If you have a mercury thermometer, don’t throw it in your household bin.
How is fever treated?
If you have a high temperature there are several things you can do to help manage your condition.
It's important to stay well hydrated. Try to drink plenty of clear, non-alcoholic fluids, such as:
Wear lightweight clothing, and avoid using bedding such as blankets, doonas and quilts. These can make you too hot and increase your temperature. Keep the room at a comfortable temperature.
Avoid taking cold baths or sponging. This can actually make you feel more uncomfortable.
If you have a fever, you should rest and avoid heavy activity until your symptoms go away. If your fever doesn’t go away, or you are concerned, see your doctor.
Fever in children
If you are caring for a sick child, learn more about fever and high temperature in children here or view this infographic.
Don’t take medicines for fever unless you are experiencing discomfort.
If you’re experiencing discomfort, you can consider pain relief medicines such as:
Before taking any medicine, you should check that it's safe to take them:
- with any medical conditions that you may have
- with any other medicines that you are taking
- if you are pregnant or breastfeeding
To check this, read the information leaflet inside the medicine packet. You can also ask a pharmacist.
When should I see my doctor?
Adults with a fever should see a doctor straight away if they have symptoms such as:
- a severe headache
- sensitivity to bright light
- an unusual skin rash
- a stiff neck
- difficulty breathing
- abdominal (tummy) pain
- seizures or muscle spasms
If your child has a fever, see a doctor right away if they:
- are under 3 months
- are getting sicker
- seem dehydrated or won’t drink
- are vomiting
- are drowsy or unresponsive
- have difficulty breathing
- seem very distressed
FIND A HEALTH SERVICE — The Service Finder can help you find doctors, pharmacies, hospitals and other health services.
Can fevers be prevented?
If your fever doesn’t go away, or you experience other symptoms mentioned above, you can prevent further complications by seeking medical attention.
Lowering or preventing a fever won’t help treat the cause of your fever.
Resources and Support
You can call the healthdirect helpline on 1800 022 222 (known as NURSE-ON-CALL in Victoria). A registered nurse is available to speak with 24 hours a day, 7 days a week.
Learn more here about the development and quality assurance of healthdirect content.
Last reviewed: February 2023