Fever in Adults: What's Normal & When to Worry

A fever — a temporary rise in body temperature — is usually a sign your body is fighting an infection. In most cases it's not dangerous in itself and settles as you recover, but knowing when a fever needs attention takes the worry out of it.

In adults, a temperature at or above about 38°C (100.4°F) is generally considered a fever. How you feel matters alongside the number — most mild fevers can be managed at home with rest, fluids, and time.

Rest, drink plenty of fluids, and dress comfortably. Over-the-counter fever reducers can help you feel more comfortable if appropriate for you. The aim is comfort and hydration while your body does its work.

Seek care if a fever is very high, lasts more than a few days, keeps returning, or comes with concerning symptoms — a stiff neck, severe headache, difficulty breathing, persistent vomiting, confusion, a rash that doesn't fade under pressure, or if you simply feel very unwell. People with certain health conditions should seek advice sooner.

If you'd like a fever assessed, our walk-in physicians see you by appointment, often the same day, at our Surrey clinics — no family doctor required. For a medical emergency, call 911.

This is general information, not medical advice. If you're seriously unwell, seek urgent care.