CFS is a shortcut for chronic fatigue syndrome. This is a complicated disorder which is characterized by extreme fatigue which cannot be explained by any underlying medical condition. This fatigue can worsen with mental or physical activity but it does not improve with rest. This is a long – term illness. It has many different symptoms. The extreme tiredness is the most common symptom of chronic fatigue syndrome. The chronic fatigue syndrome is also known as ME (myalgic encephalomyelitis) and SEID (systemic exertion intolerance disease). In some cases, it is abbreviated as ME/CFS. The cause for this condition is not known but there are many theories which are ranging from the viral to psychological stress. There are some experts who believe that the chronic fatigue syndrome can be triggered by a combination of factors. There is not a single test which can confirm a diagnosis to chronic fatigue syndrome. You should make many different medical tests to rule out other health problems which may have similar symptoms. The treatment of chronic fatigue syndrome is focusing on the symptom relief. This condition can affect people from all ages and children are also included in it.
Symptoms of chronic fatigue syndrome
Here are signs and symptoms  of chronic fatigue syndrome:
- Extreme exhaustion lasting more than 24 hours after physical or mental exercise
- Unrefreshing sleep
- Sleep problems
- Unexplained muscle or joint pain
- Feeling dizzy or sick
- Flu – like symptoms
- Enlarged lymph nodes in your neck or armpits
- Sore throat or sore glands which are not swollen
- Fast or irregular heartbeats (heart palpitations)
- Loss of memory or concentration
- Problems thinking and remembering
There are many people who have said that the over-exercising is making their symptoms worse . The severity of the symptoms can vary a lot from day to day or even in one day. The symptoms of chronic fatigue syndrome are similar to the symptoms of many other diseases so it is very important to visit your doctor for the proper diagnosis. We know that fatigue can be a symptom of many illnesses, such as psychological disorders or infections. If you have persistent or excessive fatigue, then you should talk with your doctor.
There are some studies in which are said that people who have chronic fatigue syndrome appear to be hypertensive to even normal amounts of exercise and activity. Why this is happening in some people and in other is not happening, it is not known. There are some people who are born with predisposition for chronic fatigue syndrome which can be triggered by a combination of factors. Here are some potential triggers:
- Hormonal imbalances: There are some studies in which are said that people who have chronic fatigue syndrome can experience abnormal blood levels of hormones that are produced in the hypothalamus, adrenal glands or pituitary glands. The significance of these abnormalities is still not known. 
- Immune system problems: There are some studies in which is said that the immune systems of those people who have chronic fatigue syndrome are slightly impaired but it is not known if this impairment is enough to cause the chronic fatigue syndrome. 
- Viral infections: There are some people who develop chronic fatigue syndrome after having a viral infection so in some studies are said that some viruses can trigger the chronic fatigue syndrome. Some viruses which can trigger chronic fatigue syndrome include mouse leukemia viruses, human herpes virus 6 and Epstein – Barr virus. But there is not conclusive link between them to approve or disapprove it. 
Risk factors: Here are some factors which can increase your risk of chronic fatigue syndrome :
- Stress: It is known that difficulty managing stress can lead to the development of chronic fatigue syndrome.
- Age: This disorder can happen at any age but it is more common in people who are between 40 and 50.
- Sex: It is known fact that women are diagnosed with chronic fatigue syndrome more often than men but this maybe is happening because women are going more often to doctors so their symptoms are known.
Complications: Here are some possible complications of chronic fatigue syndrome:
- Increased work absences
- Lifestyle restrictions
- Social isolation
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