What is a fever?
A fever is a high body temperature. It's one way your body fights being sick. A fever shows that the body is responding to infection or other illnesses, both minor and severe.
A fever is a symptom, not an illness by itself. A fever can be a sign that you are ill, but most fevers are not caused by a serious problem.
You may have a fever with a minor illness, such as a cold. But sometimes a very serious infection may cause little or no fever. It is important to look at other symptoms, other conditions you have, and how you feel in general. In children, notice how they act and see what symptoms they complain of.
What is a fever temperature?
A core temperature of 100.4°F or above is considered a fever.
Teens: How can you care for a fever?
- Drink plenty of fluids to prevent dehydration. Choose water and other clear liquids. If you have to limit fluids because of a health problem, talk with your doctor before you increase the amount of fluids you drink.
- Take an over-the-counter medicine, such as acetaminophen (Tylenol), ibuprofen (Advil, Motrin) or naproxen (Aleve), to relieve your symptoms. Read and follow all instructions on the label. No one younger than 20 should take aspirin. It has been linked to Reye syndrome, a serious illness.
- Take a sponge bath with lukewarm water if a fever causes discomfort.
- Dress lightly.
- Eat light foods, such as soup.
Fever in children: When to call
Call 911 anytime you think your child may need emergency care. For example, call if:
- Your child passes out (loses consciousness).
- Your child has severe trouble breathing.
Call your doctor now or seek immediate medical care if:
- Your child is younger than 3 months and has a fever of 100.4°F or higher.
- Your child is 3 months or older and has a fever of 104°F or higher.
- Your child's fever occurs with any new symptoms, such as trouble breathing, ear pain, stiff neck, or rash.
- Your child is very sick or has trouble staying awake or being woken up.
- Your child is not acting normally.
Watch closely for changes in your child's health, and be sure to contact your doctor if:
- Your child is not getting better as expected.
- Your child is younger than 3 months and has a fever that has not gone down after 1 day (24 hours).
- Your child is 3 months or older and has a fever that has not gone down after 2 days (48 hours). Depending on your child's age and symptoms, your doctor may give you different instructions. Follow those instructions.
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