Common Health Questions

What is a fever (high temperature) in children?

As a general rule, a temperature of over 37.5C (99.5F) is classified as a fever.

You can use a thermometer to find out if your child has a fever. For more information, see How do I take someone’s temperature?

Causes of fever

Most fevers are caused by an infection or another illness.

Fever helps your body fight infections by stimulating the body’s natural defences. By increasing the body’s temperature, a fever makes it harder for the bacteria and viruses that cause infections to survive.

There are many conditions that can cause fever. Most fevers are cause by a viral illness that will get better by itself without any specific treatment. Occasionally a fever may be caused by more serious infection, such as pneumonia or meningitis.

Don’t try to reduce your child’s fever by over or under dressing them, or sponging them with water. You can use paracetamol or ibuprofen to treat any distress or discomfort caused by the fever and being unwell. Read more information about giving your child paracetamol and ibuprofen.

Getting help

If you’re worried about your child, trust your instincts. Speak to your GP or if they aren't open, call NHS 24 on 111.

If you’re still concerned take your child to the nearest hospital’s accident and emergency (A&E) department.

Symptoms of serious illness

Symptoms that may be a sign of a more serious illness include:

  • being unusually sleepy
  • poor feeding
  • having a non-blanching rash (a rash that doesn’t fade when a glass is pressed firmly against the skin; this is known as the glass test)
  • a continuous or high-pitched cry 

Febrile seizures

Febrile seizures (or fits) sometimes happen in children who have a high temperature, but are a rare occurrence. Read more about febrile seizures.

Read the answers to more questions about children’s health.

Further information:

Last Updated: 14 April 2016