cfs         fatigue         home page


Chronic Tiredness also known as
Chronic Fatigue Syndrome

A person with Chronic Fatigue Syndrome also known as 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 or ME.

What causes CFS?

The cause or causes of CFS remain unknown, despite a vigorous search. While a single cause for CFS may yet be identified, another possibility is that CFS represents a common endpoint of disease resulting from multiple causes. As such, it should not be assumed that any of the possible causes listed below has been formally excluded, or that these largely unrelated possible causes are contradictory. Conditions that have been proposed to trigger the development of CFS include virus infection or other traumatic conditions, stress, and toxins.

Infectious Agents

Due, in part, to its similarity to acute or chronic infections, CFS was initially thought to be caused by a virus (i.e., Epstein-Barr (EBV) mononucleosis). It now seems clear that CFS is not caused exclusively by any single recognized infectious disease agent. CDC's four-city surveillance study found no association between CFS and infection by a wide variety of human pathogens, including EBV, human retro viruses, human herpes virus 6, enteroviruses, rubella, Candida albicans, and more recently borna viruses and Mycoplasma. Taken together, these studies suggest that among identified human pathogens, there appears to be no one pathogen that causes CFS. The recent report on finding XMRV in persons with CFS is awaiting confirmation from other researchers and in other populations.

However, the possibility remains that CFS may have multiple causes leading to a common endpoint, in which case some viruses or other infectious agents might have a contributing role for a subset of CFS cases. Recently published research suggests that infection with Epstein-Barr virus, Ross River virus and Coxiella burnetti will lead to a post-infective condition that meets the criteria for CFS in approximately 12% of cases. The severity of the acute illness was the only factor found to predict which individuals would have persistent symptoms characteristic of CFS at the six-month and one-year period following infection.


It has been proposed that CFS may be caused by an immunologic dysfunction, for example inappropriate production of cytokines, such as interleukin-1, or altered capacity of certain immune functions. As of today, one thing is certain: there are no immune disorders in CFS patients on the scale traditionally associated with disease. Some investigators have observed anti-self antibodies and immune complexes in many CFS patients, both of which are hallmarks of autoimmune disease. However, no associated tissue damage typical of autoimmune disease has been described in patients with CFS. The opportunistic infections or increased risk for cancer observed in persons with immunodeficiency diseases or in immunosuppressed individuals is also not observed in CFS. Several investigators have reported lower numbers of natural killer cells or decreased natural killer cell activity among CFS patients compared with healthy controls, but others have found no differences between patients and controls.

T-cell activation markers have also been reported to have differential expression in groups of CFS patients compared with controls, but again, not all investigators have consistently observed these differences.

One intriguing hypothesis is that various triggering events, such as stress or a viral infection, may lead to the chronic production of cytokines and then to CFS. Administration of some cytokines in therapeutic doses is known to cause fatigue, but no characteristic pattern of chronic cytokine secretion has ever been identified in CFS patients.

Finally, several studies have shown that CFS patients are more likely to have a history of allergies than are healthy controls. Allergy could be one predisposing factor for CFS, but it cannot be the only one, since not all CFS patients have it. Many patients do report intolerances for certain substances that may be found in foods or over-the-counter medications, such as alcohol or the artificial sweetener aspartame.

Hypothalamic-Pituitary Adrenal (HPA) Axis

Multiple laboratory studies have suggested that the central nervous system may have an important role in CFS. Physical or emotional stress, which is commonly reported as a pre-onset condition in CFS patients, alters the activity of the hypothalamic-pituitary-adrenal axis, or HPA axis, leading to altered release of corticotrophin-releasing hormone (CRH), cortisol and other hormones. CRH influence the immune system and many other body systems. They may also affect several aspects of behavior.

Recent studies revealed that CFS patients often produce lower levels of cortisol than do healthy controls. Similar hormonal abnormalities have been observed by others in CFS patients and in persons with related disorders like fibromyalgia. Cortisol suppresses inflammation and cellular immune activation, and reduced levels might relax constraints on inflammatory processes and immune cell activation. As with the immunologic data, the altered cortisol levels noted in CFS cases fall within the accepted range of normal, and only the average between cases and controls allows the distinction to be made. Therefore, cortisol levels (under normal conditions) cannot be used as a diagnostic marker for an individual with CFS.

A placebo-controlled trial, in which 70 CFS patients were randomized to receive either just enough hydrocortisone each day to restore their cortisol levels to normal or placebo pills for 12 weeks, concluded that low levels of cortisol itself are not directly responsible for symptoms of CFS, and that hormonal replacement is not an effective treatment. However, additional research into other aspects of neuroendocrine correlates of CFS is necessary to fully define this important, and largely unexplored, field.

Neutrally Mediated Hypo tension

Rowe and coworkers conducted studies to determine whether disturbances in the autonomic regulation of blood pressure and pulse (neutrally mediated hypo tension, or NMH) were common in CFS patients. The investigators were alerted to this possibility when they noticed an overlap between their patients with CFS and those who had NMH. NMH can be induced by using tilt table testing, which involves laying the patient horizontally on a table and then tilting the table upright to 70 degrees for 45 minutes while monitoring blood pressure and heart rate. Persons with NMH will develop lower blood pressure under these conditions, as well as other characteristic symptoms, such as light-headedness, visual dimming, or a slow response to verbal stimuli. Many CFS patients experience lightheadedness or worsened fatigue when they stand for prolonged periods or when in warm places, such as in a hot shower. These conditions are also known to trigger NMH.

Neutrally mediated hypo tension and/or postural tachycardia syndromes share some of the symptoms of CFS. They should be considered if symptoms are common with changes in position, after eating, unusual amounts of or inadequate fluid intake, or increases in activity. Current evidence does not support these conditions as being universally present in patients with CFS.

Nutritional Deficiency

There is no published scientific evidence that CFS is caused by a nutritional deficiency. While evidence is currently lacking for nutritional defects in CFS patients, it should also be added that a balanced diet can be favorable to better health in general and would be expected to have beneficial effects in any chronic illness.

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, 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.

How common is CFS? Who gets it?

Experts think at least one million Americans have CFS. Fewer than 20% 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.

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. 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.

How is CFS treated?

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:

Lifestyle Changes:

Women Handling Stress

As women, we tend to carry a high burden of stress. Don’t let stress make you sick! Here are some ways to help you handle stress.

Remember: Sometimes it is not always worth the stress to argue. Give in once in awhile.


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. 

What can I do to cope 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:

What if I can't work because of CFS?

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.

What is the latest research on CFS?

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.