A fever is a higher-than-normal body temperature. It is a part of the body's natural response to infection.
The average normal body temperature is 98.6° Fahrenheit (or 37° Celsius). When your body's temperature rises a few degrees above normal, it is a sign that your body is fighting infection and is generally not cause for concern.
In these cases, a fever is the response you want your body to have since it means that it is healthy enough to fight infection. For this reason it is not always a good idea to try and bring a fever down too quickly. However, a fever that goes above 102°F (38.9° C) should be treated.
Symptoms of a fever include:
A fever has many causes and can be a symptom of almost any illness. Among the most common are:
However, if you or a loved one are experiencing a higher-than-normal body temperature and no other symptoms of illness, do not assume something is wrong. A person's body temperature changes throughout the day and varies with many normal activities and emotions. For example, stress, excitement, wearing extra clothing, food, certain medications, a woman's menstrual cycle and exercise can all raise body temperature. Also, children tend to have a slightly higher body temperature than adults.
The best way to measure body temperature is using a thermometer inserted orally, rectally, axillary (under the arm), or by using a special instrument commonly sold in stores that is inserted in the ear and measures the temperature of the eardrum.
If your fever is mild (less than 101°F ), then no medical treatment is required. Simply make sure that you drink plenty of fluids no alcohol – and get plenty of rest. For higher temperatures, there are many effective approaches to getting your fever under control. The most common approaches include medications such as aspirin, acetaminophen, and ibuprofen. If you have a child under age 17 who has a fever, DO NOT give the child aspirin. Aspirin in children may cause Reye's syndrome, a sometime fatal illness. Taking a lukewarm bath (around 98°F ) may also help bring the body's temperature down.
If any of the following situations apply, call a doctor as soon as possible:
Any fever in an adult that goes above 105°F (or 40.5°C) and does not come down with treatment is a life-threatening medical emergency and 9-1-1 should be called.
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This information is provided by the Cleveland Clinic and is not intended to replace the medical advice of your doctor or healthcare provider. Please consult your healthcare provider for advice about a specific medical condition. This document was last reviewed on: 01/23/2019