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Fever in Adults


  • Fever is a rise in body temperature higher than the normal. A body temperature of more than 38.3 degrees Celsius (101 degrees Fahrenheit) may be considered as having a fever. A normal body temperature may be affected by different things, such as time of day or weather. A women's body temperatures may also be affected by her monthly period. The normal oral (mouth) temperature for an adult is 37 degrees Celsius (98.6 degrees Fahrenheit). Fever is usually caused by an infection due to germs, such as bacteria, viruses, or fungi. It may also be a result of an allergy, heat exposure, cancer or other diseases, or occur after using certain medicines. The cause of a fever may also be unknown, and may be called fever of unknown origin.
  • You may have red, warm, sweaty skin and you may feel hot when you have fever. At some point, you may feel cold and have chills. You may have nausea (upset stomach), vomiting (throwing up), or a headache. Other signs and symptoms may also be present pointing to the illness or condition causing the fever. Diagnosing the cause of fever will need a complete health history and physical exam, and blood and urine tests. Other tests may be done related to a disease or condition that may be causing your symptoms. Treatment will depend on the condition causing the fever. Treatment may include medicines and other measures to decrease your body temperature. With early diagnosis, treatment, and care, your fever may resolve without leading to further problems.



  • Keep a current list of your medicines: Include the amounts, and when, how, and why you take them. Take the list or the pill bottles to follow-up visits. Carry your medicine list with you in case of an emergency. Throw away old medicine lists. Use vitamins, herbs, or food supplements only as directed.
  • Take your medicine as directed: Call your primary healthcare provider if you think your medicine is not working as expected. Tell him about any medicine allergies, and if you want to quit taking or change your medicine.

Ask for information about where and when to go for follow-up visits:

For continuing care, treatments, or home services, ask for more information.

Avoid spreading germs:

You can decrease your chance of getting lung infections and other illnesses by doing the following:

  • Wash your hands often with soap and water. Carry germ-killing hand lotion or gel with you when you leave the house. You can use the lotion or gel to clean your hands when there is no water available.
  • Do not touch your eyes, nose, or mouth unless you have washed your hands first.
  • Always cover your mouth when you cough. It is best to cough into a tissue or your shirtsleeve, rather than into your hand. People around you should also cover their mouths when they cough.
  • Try to avoid people who have a cold or the flu. If you are sick, stay away from others as much as possible.

Drinking liquids:

Adults should drink about 9 to 13 cups of liquid each day. One cup is 8 ounces. Good choices of liquids for most people include water, juice, and milk. Coffee, soup, and fruit may be counted in your daily liquid amount. Ask your caregiver how much liquid you should drink each day.


Rest when you feel it is needed. Slowly start to do more each day. Return to your daily activities as directed.

For more information:

Contact the following for more information:

  • American Academy of Family Physicians
    11400 Tomahawk Creek Parkway
    Leawood , KS 66211-2680
    Phone: 1- 913 - 906-6000
    Phone: 1- 800 - 274-2237
    Web Address:


  • You have a fever.
  • Your fever does not go down even after taking your medicines.
  • You have new symptoms or symptoms that are a lot worse than before.


  • You have a bad abdominal pain, vomiting, and cannot keep food down.
  • You have a convulsion (seizure), stiff neck, and cannot think clearly.
  • You have blood in your bowel movement, urine, or sputum (spit).
  • You have chest pain or trouble breathing all of a sudden.

The above information is an educational aid only. It is not intended as medical advice for individual conditions or treatments. Talk to your doctor, nurse or pharmacist before following any medical regimen to see if it is safe and effective for you.

Learn more about Fever in Adults (Discharge Care)

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Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.