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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.
CFS is sometimes called chronic fatigue and immune dysfunction syndrome (CFIDS). It is also sometimes called myalgic encephalomyelitis (mye-AL-jik en-SEFF-ah-loh-mye-LYE-tiss), or ME.
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 infection with the Epstein-Barr virus. This is the same virus that causes infectious mononucleosis (sometimes called "mono"). 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.
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, main CFS symptoms include:
The symptoms above are the main signs of CFS. CFS symptoms may also include:
Symptoms of CFS vary widely from person to person and may be serious or mild. Most symptoms cannot be seen by others, which makes it hard for friends, family members, and the public to understand the challenges a person with CFS faces. If you think you may have CFS, talk to your doctor.
Experts think at least one million Americans have CFS. Fewer than 20 percent of these cases have been diagnosed, however.
Women are four times as likely as men to develop CFS. The illness occurs most often in people ages 40 – 59. Still, people of all ages can get CFS. CFS is less common in children than in adults. Studies suggest that CFS occurs more often in adolescents than in children under the age of 12.
CFS occurs in all ethnic groups and races, and in countries around the world. People of all income levels can develop CFS, although there is evidence that it is more common in lower-income than in higher-income persons. CFS is sometimes seen in members of the same family, but there is no evidence that it is contagious. Instead, it may run in families because of a genetic link. Further research is needed to explore how this happens.
It can be hard for your doctor to diagnose CFS because there is no lab test for it. Also, many signs of CFS are also signs of other illnesses or side effects of medical treatments. All cases are diagnosed by the 1994 Centers for Disease Control (CDC) definition, which is also sometimes called the "Fukuda criteria" after the name of a leading researcher in the field. Children with CFS can be diagnosed by a new pediatric case definition, which differs from the adult definition.
If you think you may have CFS, see your doctor. Your doctor will:
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. Although CFS is not a form of depression, many patients develop depression as a result of dealing with a long-term illness.
Right now, there is no cure for CFS. But there are things you can do to feel better. Talk to your doctor about ways to ease your symptoms and deal with your tiredness. You might also try these:
Some people say their CFS symptoms get better with complementary or alternative treatments, such as massage, acupuncture, chiropractic care, yoga, stretching, or self-hypnosis. Keep in mind that many alternative treatments, dietary supplements, and herbal remedies claim to cure CFS, but they might do more harm than good. Talk to your doctor before seeing someone else for treatment or before trying alternative therapies.
Also, keep in mind that your doctor may need to learn more about CFS to better help you. If you feel your doctor doesn't know a lot about CFS or has doubts about it being a "real" illness, see another doctor for a second opinion. Contact a local university medical school or research center for help finding a doctor who treats people with CFS.
It's normal to feel cranky, sad, angry, or upset when you have an illness like CFS. Some things that might help you to feel better include:
If you can't work because of CFS, get in touch with the Social Security Administration for help with disability benefits. It can be hard to get these benefits on your own. Working with a lawyer who specializes in disability benefits could make this process easier.
Social Security Administration
Phone: 800-772-1213 (toll free)
Both the National Institutes of Health (NIH) and the Centers for Disease Control and Prevention (CDC) fund CFS studies. Today, we have a much better understanding of CFS, but researchers are still searching for the cause(s). They also are looking for ways to prevent CFS and for the best ways to ease CFS symptoms. In time, research findings will be used to develop a cure for CFS.
For more information about chronic fatigue syndrome, call womenshealth.gov at 800-994-9662 (TDD: 888-220-5446) or contact the following organizations:
Chronic fatigue syndrome fact sheet was reviewed by:
Leonard A. Jason, Ph.D.
Center for Community Research
Content last updated July 16, 2012.
Resources last updated September 22, 2009.