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A fever of unknown origin is a temperature that reaches 101°F on and off for at least 3 weeks with no known cause. Fever is a symptom of another condition, so your health care provider will continue do tests, to narrow down the causes and determine how to treat the underlying illness. In up to 50% of cases, however, no cause is found.
Your health care provider may prefer not to give you medication while your fever remains undiagnosed. Research suggests that fever helps fight off infections. Treating the fever without knowing the cause might reduce your body's ability to deal with the possible infection. However, health care providers will prescribe drugs to reduce fever in children who suffer seizures caused by fever (febrile seizures). Because a higher temperature increases your need for oxygen, your health care provider may prescribe fever reducing medicines if you have heart or lung problems.
Signs and Symptoms
What Causes It?
Fever is a symptom of several conditions. In general, infection accounts for about 16% of cases of fever of unknown origin, followed by tumors (neoplasms) and noninfectious inflammatory diseases such as rheumatoid arthritis. Health care providers can use a series of tests to try to narrow down the list of possible reasons for a high temperature.
What to Expect at Your Provider's Office
A health care provider trying to diagnose the cause of a fever of unknown origin must look for every possible clue. The provider may ask you questions about:
Your health care provider will also examine you closely, paying particular attention to your skin, eyes, nails, lymph nodes, heart, and abdomen. The health care provider will also take blood and urine samples. You may have an ultrasound, computed tomography (CT) scan, magnetic resonance imaging (MRI), and Positron Emission Tomography (PET). If the cause of the fever is still unknown, your health provider may want to inject you with "labeled white blood cells." These are white blood cells that contain a harmless radioactive compound. Once injected, the white blood cells travel to infected parts of your body. The radioactivity allows your provider to see on an x-ray where the cells have moved. This may show the location of the infection responsible for your fever. If that test shows no results, your health provider may want to perform minor surgery to take biopsy samples of, for example, your liver or bone marrow.
Your health care provider will advise you to rest and drink plenty of fluids. You may be asked to stop taking medications for other ailments, because those medications may be causing your fever. If you have a heart or lung problem, or in the case of a child who has seizures as a result of fever, your health care provider will probably prescribe over the counter remedies to bring the temperature down.
Complementary and Alternative Therapies
General immune support with nutrition and herbs may alleviate fevers. Most natural medicine practitioners will treat fever as a sign that the body is trying to heal itself, rather than as an illness. In addition, most natural therapies attempt to support the body’s own healing processes rather than suppress the fever. It is important to speak to your medical doctor about any natural therapies you may be considering. Prolonged fever can be dangerous, and some natural therapies and conventional medications can have dangerous interactions.
Nutrition and Supplements
These nutritional tips may help improve immunity:
You may address nutritional deficiencies with the following supplements:
Herbs are generally a safe way to strengthen and tone the body's systems. As with any therapy, you should work with your health care provider to choose the safest and most effective herbal therapies before starting any treatment. You may use herbs as dried extracts (capsules, powders, teas), glycerites (glycerine extracts), or tinctures (alcohol extracts). Unless otherwise indicated, make teas with 1 tsp. herb per cup of hot water. Steep covered 5 - 10 minutes for leaf or flowers, and 10 - 20 minutes for roots. Drink 2 - 4 cups per day. You may use tinctures alone or in combination as noted.
The following herbs may help reduce fever and improve immune response:
Although few studies have examined the effectiveness of specific homeopathic therapies, professional homeopaths may consider the following remedies for the treatment of fevers based on their knowledge and experience. Before prescribing a remedy, homeopaths take into account a person's constitutional type -- your physical, emotional, and psychological makeup. An experienced homeopath assesses all of these factors when determining the most appropriate treatment for each individual.
Acupuncture may help support immune function.
Fever can be dangerous if you are pregnant. Nutritional, herbal, and homeopathic treatments for fevers are generally safe in pregnancy, yet you should use them with caution.
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Review Date: 4/4/2012
Reviewed By: Steven D. Ehrlich, NMD, Solutions Acupuncture, a private practice specializing in complementary and alternative medicine, Phoenix, AZ. Review provided by VeriMed Healthcare Network.
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