High temperature (fever) in adults

What is a high temperature?

Normal body temperature is different for everyone and changes during the day.

A high temperature is usually considered to be 38C or above. This is sometimes called a fever.

Many things can cause a high temperature, but it's usually caused by your body fighting an infection.

Check if you have a high temperature

You may have a high temperature if:

  • your chest or back feel hotter than usual
  • you have other symptoms, such as shivering (chills), sweating or warm, red skin
  • a thermometer says your temperature is 38C or above

Could it be coronavirus (COVID-19)?

A high temperature could be COVID-19.

Get advice about symptoms of COVID-19 and what to do

Do I need to take my temperature?

You do not need to take your temperature using a thermometer, but you can if you have one.

Make sure you use it correctly to help get an accurate result. See how to take a temperature.

Important

If you feel hot or shivery, you may have a high temperature even if a thermometer says your temperature is below 38C.

Treating a high temperature

It can help to:

  • get lots of rest
  • drink plenty of fluids (water is best) to avoid dehydration – drink enough so your pee is light yellow and clear
  • take paracetamol or ibuprofen if you feel uncomfortable

Advice for children

This page is for adults. For advice about children, see fever in children.