What is Chronic Fatigue Syndrome (CFS)?

A person with CFS feels completely worn-out and overtired. This extreme tiredness makes it hard to do the daily tasks that most of us do without thinking - like dressing, bathing, or eating. Sleep or rest does not make the tiredness go away. It can be made worse by moving, exercising, or even thinking.

CFS can happen over time or come on suddenly. People who get CFS over time get more and more tired over weeks or months. People who get CFS suddenly feel fine one day and then feel extremely tired the next. A person with CFS may have muscle pain, trouble focusing, or insomnia (not being able to sleep). The extreme tiredness may come and go. In some cases the extreme tiredness never goes away. The extreme tiredness must go on for at least 6 months before a diagnosis of CFS can be made.

What causes CFS?

No one knows for sure what causes CFS. Many people with CFS say it started after an infection, such as a cold or stomach bug. It also can follow a bout of infectious mononucleosis (mono), the "kissing disease" that drains your energy. Some people with CFS say it started after a time of great stress, such as the loss of a loved one or major surgery.

It can be hard to figure out if a person has CFS because extreme tiredness is a common symptom of many illnesses. Also, some medical treatments, such as chemotherapy, can cause extreme tiredness.

What are the signs of CFS?

The signs of CFS can come and go or they can stay with a person. At first, you may feel like you have the flu. As well as extreme tiredness and weakness, CFS symptoms include:

• forgetting things or having a hard time focusing
• feeling tired even after sleeping
• muscle pain or aches
• pain or aches in joints without swelling or redness
• feeling discomfort or "out-of-sorts" for more than 24 hours after being active
• headaches of a new type, pattern, or strength
• tender lymph nodes in the neck or under the arm
• sore throat

Many people with CFS report other symptoms too, ranging from a constant cough to feelings of depression. If you think you may have CFS, talk to your doctor.

How common is CFS? Who gets it?

Experts think as many as half a million Americans have a CFS-like condition. The exact number of people with CFS is not known. CFS can affect people of all ages, racial/ethnic backgrounds, and economic statuses.

More women than men are diagnosed with CFS. But, it is not known for sure that this illness affects more women than men. It may be that women talk to their doctors more often about things like tiredness and pain.

How would my doctor know if I have CFS?

It can be hard for your doctor to diagnose CFS because there is no lab test for it. And many signs of CFS are also signs of other illnesses or medical treatments.

If you think you may have CFS, see your doctor. Your doctor will:

• ask you about your physical and mental health
• do a physical exam
• order urine and blood tests, which will tell your doctor if something other than CFS might be causing your symptoms
• order more tests, if your urine and blood tests do not show a cause for your symptoms
• classify you as having CFS if:

1. you have been extremely tired for 6 months or more and tests do not show a cause for your symptoms and

2. you have 4 or more of the symptoms listed in the section "What are the signs of CFS?" in this FAQ

This process can take a long time (even years), so try to be patient with your doctor. While these tests are being done, talk to your doctor about ways to help ease your symptoms.

Tags: Chronic Fatigue Syndrome and Fibromyalgia

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