Fever In Adults

What is fever?

Fever is a rise in body temperature higher than normal. A body temperature 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. Women's body temperatures may also be affected by their monthly periods. An adult has an average normal oral (mouth) temperature of 37 degrees Celsius (98.6 degrees Fahrenheit). Fever is not a disease but a common sign of illness, infection, or other conditions.

What causes fever?

Fever is usually caused by an infection due to germs such as bacteria, viruses, or fungi. Fever is common with infections of the respiratory (breathing) system, urinary system, or skin. More serious infections such as those that affect the brain, spinal cord, abdomen (stomach), or blood can also cause a fever. Other causes of fever may include any of the following:

• Allergic reactions, such as in blood transfusions or problems with organ transplants.
  
  
• Cancer.
  
  
• Certain medicines or poisons.
  
  
• Diseases or conditions that cause inflammation (swelling), such as rheumatoid arthritis.
  
  
• Exposure to heat for a long period of time.

Sometimes, the exact cause of fever may not be known. This may be called fever of unknown origin (FUO). FUO is considered only if the fever does not go away for more than three weeks.

What are the signs and symptoms that come with fever?

You may have red, warm, sweaty skin, and you may feel hot. At some point, you may feel cold and have chills. You may be very tired, weak, or may have muscle aches. There may be nausea (upset stomach), vomiting (throwing up), or headache. Other signs and symptoms may also be present pointing to the disease or condition causing the fever.

How is fever diagnosed?

Your caregiver will take a detailed health history from you. This includes information on when you got the fever, and how long you have had it. Caregivers may ask you for information about past travel or activities, where you have been and who you have been with. They may also ask about the medicines that you use or have used. You may need any of the following:

• Physical exam: Your caregiver will do a complete check-up of your body to look for problems or signs of infection. This may include your skin, ears, mouth, neck, chest, and abdomen. Your caregiver may use different instruments to do a complete physical exam.
  
  
• Blood tests: You may need blood taken to give caregivers information about how your body is working. The blood may be taken from your hand, arm, or IV.
  
  
• Urine sample: For this test you need to urinate into a small container. You will be given instructions on how to clean your genital area before you urinate. Do not touch the inside of the cup. Follow instructions on where to place the cup of urine when you are done.
  
  
• Culture: This is a test to grow and identify the germ that is causing your fever. Samples may be taken from your nose, throat, urine, or stool (bowel movement). A culture may also be done using blood, sputum (phlegm), or swabs from a wound. It helps caregivers learn what kind of infection you have and what medicine is best to treat it.
  
  
• Other tests: Other tests may be done related to a disease or condition for which fever is a symptom. This may be based on your health history, the pattern of your fever, and signs and symptoms that go with it. It may also be based on the findings he got from your physical exam. You may have any of the following:
  
  
  • Computerized tomography scan: This test is also called a CT scan. A special x-ray machine uses a computer to take pictures of your body. It may be used to look at bones, muscles, brain tissue, and blood vessels. You may be given dye by mouth or in an IV before the pictures are taken. The dye may help your caregiver see the pictures better. People who are allergic to iodine or shellfish (lobster, crab, or shrimp) may be allergic to some dyes. Tell your caregiver if you are allergic to shellfish, or have other allergies or medical conditions.
    
    
  • Echocardiogram: This test is a type of ultrasound. Sound waves are used to show the structure, movement, and blood vessels of your heart.
    
    
  • Lumbar puncture: This procedure may also be called a spinal tap. During a lumbar puncture, you will need to lie very still. Caregivers may give you medicine to make you lose feeling in a small area of your back. Caregivers will clean this area of your back. A needle will be put in, and fluid removed from around your spinal cord. The fluid will be sent to a lab for tests. The tests check for infection, bleeding around your brain and spinal cord, or other problems. Sometimes medicine may be put into your back to treat your illness.
    
    
  • Magnetic resonance imaging: This test is also called MRI. During the MRI, pictures are taken of your body. An MRI may be used to look at the brain, muscles, joints, bones, or blood vessels. You will need to lie still during a MRI. Never enter the MRI room with an oxygen tank, watch, or any other metal objects. This can cause serious injury.
    
    
  • Ultrasound: An ultrasound is a simple test that looks inside of your body. Sound waves are used to show pictures of your organs and tissues on a TV-like screen.
    
    
  • X-rays: X-rays of different parts of your body may be taken. These may include the chest (lungs and heart) or abdomen. X-rays may help caregivers look for infections or signs of other problems. You may have more than one x-ray taken for tests.

How is fever treated?

Treatment will depend on the condition causing the fever. A virus infection often goes away on its own. Caregivers usually suggest resting in bed and drinking a lot of fluids. Medicines may be given to relieve fever and other symptoms, such as headaches or muscle pain. Caregivers may give antibiotics to treat a bacterial infection or antifungal medicine for infections caused by fungi. If you are using medicines or treatments that have been found to be causing your fever, they may need to be stopped.

Where can I find 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: http://www.aafp.org
  

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.

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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.

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