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Symptom guide

Fever

Fever is a normal immune response, not a disease by itself. For most adults a temperature under 39 °C (102 °F) can be managed at home with rest and fluids. In infants under 3 months, any fever is an emergency.

Aligned with WHO · CDC · NHS guidance

When to seek emergency care

  • Any fever in an infant under 3 months old.
  • Fever with a stiff neck, severe headache, or rash that does not fade under pressure.
  • Fever with confusion, difficulty breathing, chest pain, or seizures.
  • Fever above 40 °C (104 °F) that is not coming down with paracetamol or ibuprofen.
  • Fever lasting more than 3 days in an adult or more than 24 hours in a young child.

Safe self-care at home

  • Rest and drink plenty of fluids (water, oral rehydration solution, clear broth).
  • Dress in light layers — overwrapping can trap heat.
  • Consider paracetamol or ibuprofen at standard dosing if you have taken them safely before.
  • Monitor temperature every 2–4 hours and note any new symptoms.

When to see a clinician

  • The person is very young, elderly, pregnant, or immunocompromised.
  • Fever is accompanied by shortness of breath, chest pain, or confusion.
  • There are red-flag symptoms listed above.

Frequently asked questions

At what temperature is it officially a fever?

In adults and older children, a fever is generally defined as a body temperature of 38 °C (100.4 °F) or higher measured orally. In infants the threshold is the same but any fever under 3 months is urgent.

Can I give paracetamol and ibuprofen together?

They can be alternated in certain situations, but it depends on age, weight, and other medications. Do not combine them without guidance from a clinician or pharmacist.

Does a high fever cause brain damage?

Brain damage from fever itself is extremely rare. Most concerning fevers are signals of an underlying infection that needs evaluation — the fever number alone is not the danger.

Should I use a cold bath to bring a fever down?

No. Cold baths can cause shivering, which actually raises core temperature. Lukewarm sponging and light clothing are safer.

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This page is general patient education aligned with WHO, CDC, and NHS public guidance. It is not a diagnosis, prescription, or substitute for care from a licensed clinician. If symptoms are severe, worsening, or you are in doubt, contact a healthcare provider or your local emergency number immediately.