Chronic fatigue syndrome is a condition of prolonged and severe tiredness or weariness (fatigue) that is not relieved by rest and is not directly caused by other conditions. To be diagnosed with this condition, your tiredness must be severe enough to decrease your ability to participate in ordinary activities by 50%.
Symptoms of CFS are similar to those of most common viral infections (muscle aches, headache, and fatigue). They come on within a few hours or days and last for 6 months or more.
•Fatigue or tiredness, never experienced to this extent before (new onset), lasting at least 6 months and not relieved by bed rest
•Fatigue that is severe enough to restrict activity (serious fatigue develops with less than one-half of the exertion compared with before the illness)
•Fatigue lasting more than 24 hours after an amount of exercise that would normally be easily tolerated
•Feeling unrefreshed after sleeping an adequate amount of time
•Forgetfulness or other similar symptoms including difficulty concentrating, confusion, or irritability
•Headaches, different from previous headaches in quality, severity, or pattern
•Joint pain, often moving from joint to joint (migratory arthralgias), without joint swelling or redness
•Lymph node tenderness in the neck or armpit
•Mild fever (101 degrees F or less)
•Muscle aches (myalgias)
•Muscle weakness, all over or multiple locations, not explained by any known disorder
Causes & Risk Factors
The exact cause of chronic fatigue syndrome (CFS) is unknown. Some researchers suspect it may be caused by a virus, such as Epstein-Barr virus or human herpes virus-6 (HHV-6). However, no specific virus has been identified as the cause.
Studies suggest that CFS may be caused by inflammation along the nervous system, and that this inflammation may be some sort of immune response or process.
Other factors such as age, prior illness, stress, environment, or genetics may also play a role.
CFS most commonly occurs in women ages 30 to 50.
The Centers for Disease Control (CDC) describes CFS as a distinct disorder with specific symptoms and physical signs, based on ruling out other possible causes. The number of persons with CFS is unknown.
Tests & Diagnostics
Physical examination may confirm fever, lymph node tenderness, lymph node swelling, or other symptoms. The throat may appear red without drainage or pus.
The health care provider will diagnose chronic fatigue syndrome (CFS) only after ruling out all other known possible causes of fatigue, such as:
•Immune or autoimmune disorders
•Muscle or nerve diseases (such as multiple sclerosis)
•Endocrine diseases (such as hypothyroidism)
•Other illnesses (such as heart, kidney, liver diseases)
•Psychiatric or psychological illnesses, particularly depression (since CFS itself may be associated with depression, a diagnosis of depression does not rule out CFS but fatigue related to depression alone must be ruled out for CFS to be diagnosed)
A diagnosis of CFS must include:
•Absence of other causes of chronic fatigue (excluding depression)
•At least four of the other symptoms listed
•Extreme, prolonged fatigue
There are no specific tests to confirm the diagnosis of CFS, although a variety of tests are usually done to exclude other possible causes of the symptoms.
The following test results, while not specific enough to diagnose CFS, are seen consistently in people who are eventually diagnosed with the disorder:
•Brain MRI showing swelling in the brain or destruction of part of the nerve cells (demyelination)
•Higher levels of specific white blood cells (CD4 T cells) compared with other types of white blood cells (CD8 T cells)
•Specific white blood cells (lymphocytes) containing active forms of EBV or HHV-6
There is currently no cure for CFS. Instead, the symptoms are treated. Many people with CFS experience depression and other psychological problems that may improve with treatment.
Some of the proposed treatments include:
•Antiviral drugs (such as acyclovir)
•Drugs to fight yeast infections (such as nystatin)
•Medications to reduce pain, discomfort, and fever
•Medications to treat anxiety (antianxiety drugs)
•Medications to treat depression (antidepressant drugs)
Some medications can cause adverse reactions or side effects that are worse than the original symptoms of chronic fatigue syndrome.
Patients with CFS are encouraged to maintain active social lives. Mild physical exercise may also be helpful.
Nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen and naproxen, may be used to relieve pain and reduce fever. Another medication that is prescribed to relieve pain and muscle spasms is cyclobenzaprine (Flexeril).
Many doctors prescribe low dosages of antidepressants for their sedative effects and to relieve symptoms of depression. Antianxiety drugs, such as benzodiazepines or buspirone may be prescribed for excessive anxiety that has lasted for at least six months.
Other medications that have been tested or are being tested for treatment of CFS are:
•Fludrocortisone (Florinef), a synthetic steroid, has helped some CFS patients who have neurally mediated hypotension.
•Beta-adrenergic blocking drugs, including atenolol (Tenoretic, Tenormin) and propranolol (Inderal), are sometimes prescribed for neurally mediated hypotension.
•Gamma globulin, which contains human antibodies has been used experimentally to boost immune function in CFS patients.
•Ampligen, a drug which stimulates the immune system and has antiviral activity, improved mental function in CFS patients.
The following supplements have been used in treating CFS.
•Vitamin B12 deficiency causes fatigue, muscle aches, confusion, poor memory, and arm and leg numbness.
•Magnesium helps muscles to relax. Persons with kidney or heart disease should not take magnesium.
•Iron treats anemia, which can cause tiredness, and improve mental clarity. This should only be taken if a physician has diagnosed an iron deficiency.
•Manganese works with the supplements above to relieve CFS symptoms.
•Copper deficiency can cause inflammation. Maximum recommended daily dose for adults is 2–3 mg. Pregnant women should consult a physician before taking copper supplements.
•Zinc may boost the immune system.
•Coenzyme Q10 can increase immune health.
•NADH led to improvement in energy, cognitive ability, sleep patterns, headaches, and depression in a small study of CFS patients.
•Carnitine helps to better utilize fats for energy production. The recommended daily dose is 500–3,000 mg.
•Alpha lipoic acid enhances energy.
•5-HTP helps to regulate sleep patterns.
•DHEA deficiency causes fatigue in females and low sex drive in males. It should only be taken under the direction of a physician.
Fluoride is a potentially toxic substance and should be avoided.
•Depression (related both to symptoms and lack of diagnosis)
•Lifestyle restrictions (some people are so fatigued that they are essentially disabled during the course of the illness)
•Side effects and adverse reactions to medication treatments
•Social isolation caused by fatigue
Because the cause of CFS is not known, there are no recommendations for preventing the disorder.