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Fever In Adults


What is a fever?

A fever is an increase in body temperature above 100.4°F (38°C).

What are common causes of a fever?

The cause of your fever may not be known. This is called fever of unknown origin. It occurs when you have a fever above 100.9˚F (38.3°C) for 3 weeks or more. The following are common causes of fever:

  • An infection caused by a virus or bacteria
  • An inflammatory disorder, such as arthritis
  • Severe withdrawal from alcohol or illegal drugs

What other signs and symptoms may I have?

  • Chills and shivers
  • Muscle stiffness
  • Weight loss
  • Night sweats
  • Fever that comes and goes
  • Fever that is higher in the morning

How is the cause of a fever diagnosed?

Your healthcare provider will ask when your fever began and how high it was. He will ask about other symptoms and examine you for signs of infection. He will feel your neck for lumps and listen to your heart and lungs. Tell him if you recently had surgery or an infection. Tell him if you have any medical conditions, such as diabetes. You may also need blood or urine tests to check for infection. Ask about other tests you may need if blood and urine tests do not explain the cause of your fever.

How is a fever treated?

  • Ibuprofen or acetaminophen can help decrease your fever. They are available without a doctor's order. Ask your healthcare provider how much to take and when to take it. Follow directions. These medicines can cause stomach bleeding if not taken correctly. Ibuprofen can cause kidney damage. Acetaminophen can cause liver damage.
  • Antibiotics may be given if you have an infection caused by bacteria.

What can I do to manage my fever?

  • Take a bath in cool or lukewarm water.
  • Use an ice pack wrapped in a small towel or wet a washcloth with cool water. Place the ice pack or wet washcloth on your forehead or the back of your neck.
  • Drink more liquids. Ask your healthcare provider how much liquid to drink each day and which liquids are best for you. You may also need to drink an oral rehydration solution (ORS). An ORS has the right amounts of water, salts, and sugar you need to replace body fluids.

When should I seek immediate care?

  • Your fever does not go away or gets worse even after treatment.
  • You have a stiff neck and a bad headache.
  • You are confused. You may not be able to think clearly or remember things like you normally do.
  • Your heart beats faster than normal even after treatment.
  • You have shortness of breath or chest pain when you breathe.
  • You urinate very small amounts or not at all.
  • Your skin, lips, or nails turn blue.

When should I contact my healthcare provider?

  • You have abdominal pain or feel bloated.
  • You have nausea or are vomiting.
  • You have pain or burning when you urinate, or you have pain in your back.
  • You have questions or concerns about your condition or care.

Care Agreement

You have the right to help plan your care. Learn about your health condition and how it may be treated. Discuss treatment options with your caregivers to decide what care you want to receive. You always have the right to refuse treatment. 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.

© 2015 Truven Health Analytics Inc. Information is for End User's use only and may not be sold, redistributed or otherwise used for commercial purposes. All illustrations and images included in CareNotes® are the copyrighted property of A.D.A.M., Inc. or Truven Health Analytics.