A fever is a body temperature that is higher than normal. It usually means there is an abnormal process occurring in the body. Exercise, hot weather, and common childhood immunizations can also make body temperature rise.
A fever is not an illness by itself. Rather it is a symptom that something is not right within the body. A fever does not tell you what is causing it, or even that a disease is present. It may be a bacterial or viral infection. Or, it could be a reaction from an allergy to food or medicine. Becoming overheated at play or in the sun can also result in fever.
Normal body temperature ranges from 97.5°F to 98.9°F (36.4°C to 37.2°C). It tends to be lower in the morning and higher in the evening. Most healthcare providers consider a fever to be 100.4°F (38°C) or higher. High fevers may bring on seizures or confusion in children. It's not how high the temperature is, but how fast the temperature goes up that causes a seizure.
A fever has other symptoms besides a higher-than-normal temperature. These are especially important when caring for babies, young children, and disabled people. These groups may not be able to express how they feel. Signs that mean fever include:
Taking a temperature rectally is the most accurate method in children under 3 years of age. In older children and adults, take the temperature under the armpit or in the mouth. Talk with your healthcare provider about the best way to take your temperature.
Most thermometers today are digital, but there are some glass thermometers containing mercury still in use. Mercury is toxic substance and is dangerous to humans and the environment. Because glass thermometers can break, they should be disposed of properly in accordance with local, state, and federal laws. For information on how to safely dispose of a mercury thermometer, contact your local health department, waste disposal authority, or fire department.
You can treat a fever with acetaminophen or ibuprofen in dosages advised by your healthcare provider. Switching between giving acetaminophen and ibuprofen can cause medicine errors and may lead to side effects. Never give aspirin to a child or young adult who has a fever.
A lukewarm bath may reduce the fever. Alcohol rubdowns are no longer recommended.
Call your healthcare provider for guidance anytime you are uncomfortable with the conditions of the fever, and remember to contact your healthcare provider any time a temperature spikes quickly or persists despite treatment.
Call your healthcare provider right away for a fever in a baby younger than 3 months old.
Call right away or seek immediate medical attention if any of the following occur with a fever:
Tips to help you get the most from a visit to your healthcare provider:
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