To evaluate a fever, your care provider may:
- Ask questions about your symptoms and medical history
- Perform a physical exam
- Take nasal or throat samples to test for respiratory infections
- Order tests, such as blood tests or a chest X-ray, as needed, based on your medical history and physical exam
Because a fever can indicate a serious illness in a young infant, especially two months of age or younger, your baby might be admitted to the hospital for testing and treatment.
Fever of unknown origin
When a fever lasts for more than three weeks — constantly or on several occasions — and there is no clear cause, it's usually called a fever of unknown origin. In these cases, you may need to see specialists in one or more medical fields for further evaluations and tests.
For a low-grade fever, your care provider may not recommend taking medications to lower your body temperature. These minor fevers may be helpful in reducing the number of microbes causing your illness. Fevers above 102 F (38.9 C) tend to cause discomfort and often require treatment.
In the case of a high fever or a fever that causes discomfort, your care provider may recommend nonprescription medication, such as acetaminophen (Tylenol, others) or ibuprofen (Advil, Motrin IB, others).
Use these medications according to the label instructions or as recommended by your health care provider. Be careful not to take too much. High doses or long-term use of acetaminophen or ibuprofen may cause liver or kidney damage, and acute overdoses can be fatal. Don't give aspirin to children, because it may trigger a rare, but potentially fatal, disorder known as Reye's syndrome.
These medications will usually lower your temperature, but you may still have a mild fever. It may take 1 to 2 hours for the medication to work. Call your care provider if your fever doesn't improve, even after taking medication.
Your health care provider may prescribe other medications based on the cause of your illness. Treating the underlying cause may lessen signs and symptoms, including fever.
Treatment of infants
Infants, especially those younger than two months old, might need to be admitted to the hospital for testing and treatment. In babies this young, a fever could indicate a serious infection that requires intravenous (IV) medications and round-the-clock monitoring.
You can try a number of things to make yourself or your child more comfortable during a fever:
- Drink plenty of fluids. Drinking fluids will improve heat loss from the skin and replace water lost through sweating. Water and clear broth are healthy choices. Infants under 6 months should only have breast milk or formula.
- Rest. You need rest to recover, and activity can raise your body temperature.
- Stay cool. If you aren't shivering, dress in light clothing, keep the room temperature cool, and sleep with only a sheet or light blanket.
Preparing for your appointment
Your appointment may be with your family doctor, pediatrician or other care provider. Here's some information to help you get ready for your appointment and know what to expect from your care provider.
What you can do
- Be aware of any pre-appointment restrictions. When you make the appointment, ask if there's anything you need to do in advance.
- Write down information about the fever, such as when it started, how and where you measured it (orally or rectally, for example) and any other symptoms. Note whether you or your child has been around anyone who's been ill.
- Write down key personal information, including possible exposure to anyone who's been ill or recent travel out of the country.
- Make a list of all medications, vitamins and supplements that you or your child is taking.
- Write down questions to ask the care provider.
For a fever, some basic questions to ask your provider include:
- What's likely causing the fever?
- What kinds of tests are needed?
- What treatment approach do you recommend?
- Is medicine necessary to lower the fever?
- Are there any restrictions that I need to follow?
Don't hesitate to ask other questions during your appointment as they occur to you.
What to expect from your doctor
Be prepared to answer questions, such as:
- When did the symptoms first occur?
- What method did you use to take your or your child's temperature?
- What was the temperature of the environment surrounding you or your child?
- Have you or your child taken any fever-lowering medication?
- What other symptoms are you or your child experiencing? How severe are they?
- Do you or your child have any chronic health conditions?
- What medications do you or your child regularly take?
- Have you or your child been around anyone who's ill?
- Have you or your child recently had surgery?
- Have you or your child recently traveled outside the country?
- What, if anything, seems to improve the symptoms?
- What, if anything, appears to worsen the symptoms?