A fever is when the body temperature rises higher than normal. The average body temperature is 98.6°F (37°C), but normal body temperature can range between 97°F (36.1°C) and 99°F (37.2°C) or more. Most healthcare providers consider a fever to be 100.4°F (38°C) or higher. However, some providers say a fever is either 100.0°F (37.8°C) or 100.4°F (38°C). A body temperature above 99°F to 99.5°F (37.2°C to 37.5°C), depending on the time of day, probably indicates a fever in adults. A low-grade fever is a body temperature slightly above normal, and many healthcare providers consider a body temperature between 99.5°F (37.5°C) and 100.3°F (38.3°C) to be a low-grade fever. In adults, fevers less than 103°F (39.4°C) typically aren’t dangerous and aren’t a cause for concern. If the fever lasts more than five days in a row, or if someone with a fever has any of the following signs and symptoms, medical care should be sought:
- Severe headache
- Unusual skin rash, especially if the rash rapidly worsens
- Unusual sensitivity to bright light
- Stiff neck and pain when you bend your head forward
- Mental confusion
- Persistent vomiting
- Difficulty breathing or chest pain
- Abdominal pain or pain when urinating
- Convulsions or seizures (for example, uncontrolled jerking of limbs)
- Any other unexplained or concerning symptoms
In general, if the fever is mild (less than 101°F or 38.3°C), treatment with medication is usually not necessary. Drinking plenty of fluids, getting plenty of rest, and taking a lukewarm bath (about 98°F or 36.7°C) may help bring the bodys temperature down. However, if the fever is higher than 102.2°F (39°C), it can be a sign of a more serious infection, and medical treatment should be sought.
