Fever

Higher than normal body temperature

Fever, also known as pyrexia, is a raise in body temperature above normal range. It is a common medical sign that accompanies various conditions, some mild & others more serious.
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Fever usually indicates an underlying infection of some sort. Normal body temperature is around 37°C, & any temperature of 37.5°C (99.5°F) & above is considered a fever.

Chills is a symptom that often accompanies a fever, as well as feeling cold.

Causes

The most common cause of a fever is the flu, cough or cold.

Other infections that can cause fever include:

  • Ear infections
  • Tonsillitis
  • Urinary tract or kidney infections
  • Childhood conditions like chickenpox & whooping cough

 

You may also have a raised temperature following vaccination, or from becoming overheated. Children have a harder time regulating their body temperature than adults, and can become feverish due to too much bedding or clothing.

Symptoms

  • Recurrent or constant pain in or around the eyes
  • Sudden eye pain
  • Itching or burning eyes
  • Changes in vision, such as blurring, double vision, or obstruction
  • Floaters
  • Seeing halos around lights or flashing lights
  • Photosensitivity (painful or significant sensitivity to light)
  • Swollen eyelids
  • Discharge from the eye

 

Please note that sudden, unexplainable blurred vision is an emergency, as it can indicate a stroke or a retinal detachment.

What to do next?

If you are experiencing a fever, with or without other symptoms, we recommend that you come for an appointment & a diagnosis. You can book using our online system, or give us a call during office hours to make your appointment.

020 7323 1023
Harley Street Area, W1
020 7101 0355
City of London, EC2N

Questions about Fever

When should I see a doctor for a fever?

Seek medical attention if your fever is above 39°C, lasts more than 3 days, or is accompanied by severe symptoms like difficulty breathing, chest pain, persistent vomiting, confusion, or a rash.

Is a high fever dangerous?

High fevers can be uncomfortable but are usually not dangerous on their own. Very high fevers (above 41°C) or fevers in young infants require urgent medical attention.

Can children handle fevers differently than adults?

Children’s fevers can rise quickly. Seek prompt care if a baby under 3 months has a temperature above 38°C, or if a child shows signs of distress or dehydration.

Can fever be a symptom of the flu?

Yes. Fever is a common symptom of many viral infections, including influenza. Other symptoms like cough, sore throat, or body aches may also occur.

Is fever contagious?

A fever itself is not contagious. However, the underlying cause (like a viral or bacterial infection) may be contagious.

The Harley Street Doctor

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