Fatigue syndrome

Fatigue syndrome is a common description for symptoms. It can have various causes or be a consequence of mental and physical illnesses and their treatment. It presents as a feeling of persistent fatigue, lethargy and exhaustion, and doesn't improve by getting a lot of sleep.


Fatigue syndrome is a common description for symptoms that can have various causes or be a consequence of mental and physical illnesses and their treatment. It presents as a feeling of persistent fatigue, lethargy and exhaustion, and doesn't improve by getting a lot of sleep.

Chronic fatigue syndrome (CFS) on the other hand is relatively rarely diagnosed and constitutes a disease in its own right. Doctors describe CFS as a serious, polymorphic neuroimmunological disease (neuroimmunological = affecting both the nervous and immune system). The main symptoms of CFS are extreme mental and physical fatigue and tiredness that can't be explained by an underlying physical cause or a specific mental disorder. Patients also suffer from a wide variety of other complaints.


Fatigue syndrome often occurs as a side effect of chronic illnesses such as rheumatism and cancer or as a result of extraordinary stresses such as chemotherapy. Patients feel less able to perform than before, both physically and mentally. Even everyday activities such as cleaning your teeth, making a phone call or paying close attention to something are often found to be very difficult. Fatigue patients feel exceptionally exhausted after such activities. Patients can’t improve their fatigue and exhaustion by getting a lot of sleep. They go to bed feeling exhausted and get up the next day feeling the same. Fatigue shouldn’t be confused with CFS. Although the symptoms are similar, fatigue syndrome has a different cause.

CFS patients present with different symptoms in differing degrees of severity. Chronic fatigue syndrome is mainly characterised by extreme tiredness that usually started at a definable point in time and has lasted for at least six months.

Symptoms are also similar to those of other diseases such as fibromyalgia, which is a rheumatic disease.


The diagnosis is based on a comprehensive recording of the patient's medical history. During this session, the medical history is discussed, the scope of the fatigue syndrome is measured and various physical examinations are carried out in order to exclude an organic cause.

Chronic fatigue syndrome is difficult to diagnose, and because there are no special laboratory tests or other apparatus-based tests to give a secure diagnosis of CFS, it is often not detected. In addition to a precise recording of the medical history and all symptoms, the primary goal is to identify other illnesses that can cause similar symptoms as chronic fatigue syndrome.

Possible therapies

Fatigue that is due to an organic cause such as anaemia can often be treated with medication.

Treatment is more difficult if the cause of the fatigue is totally unknown or multiple factors contribute to the fatigue. Medication as well as non-drug measures are often applied. This goes hand in hand with individual consultation intended to help patients cope better with the fatigue-related restrictions to their everyday lives.

Experts have been unable to agree on the best treatment for CFS to date. But one thing is certain: treatment should be tailored to the individual patient. It usually focuses on the symptoms that most affect the patient (e.g. sleep disorders, pain) and accompanying disorders, and should include medication as well as non-drug measures.

When to see a doctor?

You should definitely see a doctor if you’ve been experiencing tiredness for a lengthy period of time. This also applies if the tiredness occurs suddenly for no discernible reason or is considerably worse than normal.


Fatigue syndrome, chronic fatigue syndrome (CFS), chronic fatigue, chronic tiredness, CFS, myalgic ence­phalo­mye­li­tis, ME

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Exclusion of liability

CSS offers no guarantee for the accuracy and completeness of the information. The information published is no substitute for professional advice from a doctor or pharmacist.

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