Chronic fatigue syndrome


What is Chronic Fatigue Syndrome (CFS)?

Chronic Fatigue Syndrome (CFS) has in the past been known by other names, such as ME (Myalgic Encephalitis) and Post Viral Fatigue Syndrome (PVFS). It is a potentially distressing condition which is, as yet, not very well understood and results in, as its name suggests, prolonged fatigue as well as other symptoms which will be described in more detail below.

Although most people think of CFS as a modern illness, it has probably existed for many years but has been called by other names. For instance, in Victorian times a condition called 'neurasthenia' existed which had symptoms that would fit for what we now call CFS. CFS is thought to affect between 0.2 to two percent of the population at any one time and affects women (or girls) twice as often as it affects men (or boys). The most commonly affected age group is early twenties to mid forties, but it can also affect children and teenagers.

What are the symptoms of Chronic fatigue syndrome?

The main symptom of CFS is, of course, fatigue. For a diagnosis of CFS to be made, this must be unexplained fatigue of new onset that is not against a background of a lifetime of fatigue. One problem with diagnosing CFS is that fatigue is a very common symptom, experienced by everyone at one time or another and thought to affect about 30 percent of people at any one time. However, people with CFS find that their fatigue does not follow the normal pattern that those who are healthy would expect. For instance, it does not necessarily relate to having exercised and does not alleviate with rest. It is also very persistent, some doctors saying that CFS should not be considered until the fatigue has lasted at least six months.

In addition CFS is characterised by the sufferer having four or more of the following additional symptoms:

  • Impaired memory (especially short term memory) and concentration.
  • Tender lymph glands in the neck or under the arms. (Lymph glands are the soft lumps we all have in various parts of our body which exist to fight off infection).
  • New onset of headaches for no obvious reason.
  • Joint pains without swelling or muscle pains for no reason.
  • Recurring sore throats.
  • Tiredness after exercise lasting longer than 24 hours. This worsening of fatigue may be delayed, that is, may occur 24 hours or more after a period of exercise or increased mental activity.
  • Sleep difficulties such as early morning waking, disrupted sleep or unrefreshing sleep.

Other symptoms may include sensitivity to noise, bright lights or certain foods; dizziness, vertigo, palpitations, feelings of poor body temperature control, depression and panic attacks.

What is the cause of Chronic fatigue syndrome?

The cause of Chronic fatigue syndrome is not yet known. Lots of theories have been put forward but, as yet, none has been proven.

The most common theory for the cause of CFS is that it is caused by a virus. One of the reasons for this theory is that it is well known that fatigue often follows viral illnesses and certain viruses such as the Epstein Barr Virus, which causes Glandular Fever, can cause prolonged fatigue for several weeks after the original illness. A study of people who had contracted Glandular Fever showed that although most people had fully recovered within 10 weeks, about 16 percent were still complaining of fatigue six months later. This suggests that there are some people who are more prone to fatigue following viral illnesses than others, but it is not known why this is.

There are some factors that appear to make someone more likely to suffer from chronic fatigue after a severe viral infection. These include a previous history of depression or a psychiatric disorder, taking a long time off work following illnesses in general, being given a sick note by the physician (although this may simply be an indication of how severe the symptoms experienced by the patient are) and not being given a clear diagnosis.

However, against the viral theory is a study which looked at 2000 patients, half of whom presented to their physician with a viral illness and half who went for a completely different reason. When they were followed up six months later, there was no difference in the number of each group who had Chronic fatigue syndrome. Those patients who developed CFS were more likely to have suffered from fatigue or stress before they went to their doctor.

Psychological factors therefore seem to be linked in some way with CFS. This is highlighted by the findings that depression or anxiety is found in half to two thirds of patients with Chronic fatigue syndrome. Although it could be argued that this may be as a result of the CFS itself, depression and anxiety are much higher in CFS patients when compared with people with other types of physical problems causing the same level of disability.

There also seem to be personality factors involved with the development of Chronic fatigue syndrome with more so-called Type A personalities (anxious, highly motivated perfectionists) developing this condition. The connection is not understood. One theory is that these people are more prone to suffer from the stress that appears to be linked with developing this condition. It may be that these people do not take enough rest at the beginning of the illness. This then leads on to chronic fatigue.

Many other theories exist for the cause of Chronic fatigue syndrome but, as mentioned, none have been conclusively proven and in many cases it is hard to tell what is a cause of the illness and what is an effect.

How is Chronic fatigue syndrome diagnosed?

The diagnosis of Chronic fatigue syndrome can be difficult since there is no specific test for this condition. As a result the diagnosis is usually made on the basis of the symptoms described by the patient. However, the doctor making the diagnosis will almost certainly want to exclude other causes for chronic fatigue by examining the patient and performing some blood tests.

For instance, anaemia, diabetes, thyroid, and kidney conditions can cause persistent tiredness, so blood and/or urine tests will be done to rule these and other conditions out. All these blood tests will be normal in CFS as will examination of the patient.

What is the treatment of Chronic fatigue syndrome?

There is no one treatment for Chronic fatigue syndrome. Different treatments will suit different patients. However, there are three main approaches that have been found to be useful in many cases.

Graded exercise

Graded exercise aims to gradually increase the person's level of activity. This attempts to prevent the tendency of many CFS sufferers either becoming very inactive, thereby making further inactivity more likely, or the temptation to overdo their activity on their good days which almost inevitably leads to severe fatigue in the subsequent days.

However, not everyone succeeds with graded exercise and some CFS sufferers felt that it made them worse. Ideally, the rate at which exercise is increased should be tailored to the individual and supervised by a specialist physiotherapist or occupational therapist who has experience in treating the condition. It is a therapy worth considering.

Cognitive Behaviour therapy

Cognitive behaviour therapy (CBT) is based on the idea that altering the way one thinks about things can alter the effect is has on you and aims to reduce ways of thinking which are harmful or unhelpful. For instance, CBT is used in the treatment of phobias to change the person's reaction to the thing they are afraid of eg. spiders. The same type of treatment can help people to lessen the effect of the illness on their daily lives.

Studies have shown that a course of CBT sessions over a period of several months led to significant reductions in fatigue and disability in about 70 percent of CFS sufferers who took part.


Antidepressants such as fluoxetine (Prozac) are sometimes prescribed as part of the treatment of Chronic fatigue syndrome. In general they tend to be helpful for those sufferers who become depressed as part of the illness but may not be so helpful for others.

Some antidepressants such as Amitriptyline are occasionally beneficial for the treatment of chronic or recurring pain, which is sometimes a feature of CFS, and have the additional benefit of treating any co-existent depression. If muscular pain is a particular symptom then this may also be treated with anti-inflammatory medication such as ibuprofen.

Information Brand Generic Label Rating
Zoloft Zoloft Sertraline Off-Label
Elavil Drug Elavil Amitriptyline Off-Label
Paxil 20mg Paxil Paroxetine Off-Label
Zyban dosage Zyban Bupropion Off-Label
Ibuprofen Motrin Ibuprofen Off-Label

Imuran (Azathioprine), Prozac (Fluoxetin), Sinequan (Doxepin), Tofranil (Imipramine), Tenormin (Atenolol), Ambien (Zolpidem), Florinef (Fludrocortisone), Soma (Carisoprodol), Xanax (Alprazolam)

Complementary treatments

Some people find complementary therapies such as aromatherapy, acupuncture or reflexology helpful but there is very little research into how effective these are in general.

What is the likely outcome for someone with Chronic fatigue syndrome?

Most people with CFS find that their symptoms vary greatly so that there are times when the illness does not affect them too much and then, often for no obvious reason, the symptoms can suddenly become much more severe.

In the long term, most people with CFS will gradually improve with time - a significant proportion recovering within two years. However, others unfortunately continue to suffer for many years and even those who do recover are often left with lower energy levels than they had before. Having the illness for more than five years, having more severe symptoms or suffering from the condition at an older age all indicate a poorer outlook and less likelihood of the condition responding to treatment.

Chronic fatigue syndrome in children

The occurrence of Chronic fatigue syndrome in children is estimated to be between 0.05 percent and two percent, with the most commonly affected age being between 10 and 12, although it has been diagnosed in children as young as five.

In some ways the diagnosis of CFS in children is easier than in adults. This is because children do not, in general, tend to suffer from prolonged tiredness and there are fewer alternative causes for fatigue that need to be ruled out before a confident diagnosis of CFS can be made.

Chronic fatigue syndrome in children can vary from relatively mild symptoms, which only have a small effect on the life of the patient, to those whose condition is so severe that they are bed-bound and have to be fed via a tube as they do not even have enough energy to eat or feed themselves. Otherwise, the symptoms and other features are very similar to the adult form, as is the way the diagnosis is made.

The treatment of Chronic fatigue syndrome in children is very similar to that of adults although obviously educational support and support for the parents may also be required.

In general, the outcome for children with CFS is better than for adults with even the severe cases sometimes making full recoveries. However, as with adults, the condition may last several years before some recovery is seen.

Notify your physician if

  • You or a family member has signs and symptoms of chronic fatigue syndrome.
  • Symptoms worsen after treatment is started.

Last updated 21 December 2015


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