A fever is when your body temperature is higher than 38C - compared to a normal temperature of around 37C (98.6F).

By Wallace Health I Medically reviewed by Adrian Roberts.
Page last reviewed: October 2018 I Next review due: October 2023


Fever is your body’s natural reaction to infection. Your high temperature will usually return to normal as the infection passes.

A high temperature can be accompanied by other fever symptoms, including feeling:

  • Cold and shivery
  • Hot, clammy and sweaty
  • Generally unwell
  • Blood in urine

Fever is very common, especially in babies and young children. Sometimes, a child with a high temperature may have fits (febrile seizures) and become dehydrated.

You should be able to reduce the symptoms associated with a fever with simple home remedies and, if required, over-the-counter medication.

Causes of fever

In adults, causes of fever are usually common viral and bacterial infections, including coughs, cold or flu.

Rarely, in adults and children, a high fever may be a symptom of a more serious condition, including:

  • Heat exhaustion
  • A bacterial infection, such as meningitis
  • Sepsis – a potentially life-threatening complication of blood infection (septicaemia)
  • Rheumatoid arthritis
  • An anal abscess
  • Certain cancers, liver problems and kidney disease
  • Lyme disease

If your child has a high temperature, they may have:

  • A common childhood illness, such as chickenpox, tonsillitis or whooping cough
  • A cold or flu
  • A throat, chest, ear or urine infection

A fever can also be a side effect of several childhood immunisations.

Talk to your doctor if you’re concerned about symptoms

You can book an appointment with a Spire private GP today.

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Getting a diagnosis for a fever

You can check your temperature using a thermometer.

Seek urgent medical attention if your child has a high temperature and has:

  • Any of the possible symptoms of meningitis, including sensitivity to bright light, stiff and painful neck, severe headache and a rash that doesn’t fade when pressed with a glass
  • Coughing up blood
  • A fit (febrile seizure) for the first time
  • Unusually cold hands and feet or pale skin and lips

If your child has had a high temperature for over three days, contact your GP. You should also contact your GP if your child has a high fever accompanied by:

  • Other signs of illness, such as a rash, vomiting or diarrhoea
  • Signs of dehydration
  • Lack of appetite and is generally unwell
  • Being unwell or listless

You should contact your GP if you have a worryingly high fever along with:

  • Any of the possible symptoms of meningitis (see above)
  • Breathing problems and/or severe chest pain
  • Intense stomach pain
  • Difficulties urinating
  • Convulsions or seizures

After discussing symptoms and carrying out any necessary examinations, your GP should be able to diagnose the cause of your fever. However, for some underlying conditions they may need to refer you to a consultant or hospital.

Treatments for fever

To help reduce symptoms associated with a fever:

  • Drink lots of fluids
  • Take the recommended dosage of paracetamol or ibuprofen
  • Ensure your surroundings aren’t too warm and wear light clothing

If required, your doctor will be able to arrange treatment. In some cases, your doctor may prescribe medication, either to relieve fever symptoms or to treat the fever’s underlying cause.