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Chronic fatigue syndrome (Myalgic

encephalomyelitis)
Chronic fatigue syndrome (CFS), previously sometimes known as myalgic
encephalomyelitis (ME), is a condition where there is long-term disabling
tiredness (fatigue). Most people with also have one or more other
symptoms such as muscular pains, joint pains, disturbed sleep patterns,
poor concentration or headaches. The cause is not known.

What is chronic fatigue syndrome?

Chronic fatigue syndrome (CFS), which was sometimes previously referred
to as myalgic encephalomyelitis (ME), is a condition that causes marked
long-term tiredness (fatigue) and other symptoms which are not caused
by any other known medical condition.

How long does chronic fatigue syndrome last?

Chronic fatigue syndrome is a fluctuating condition in which symptoms can
change unpredictably in nature and severity over time. The impacts are
variable in severity but there can be flare-ups and relapses even if
symptoms are generally well managed.

There is no test to diagnose the condition. The diagnosis is made in people

who have a certain set of symptoms.

What are the symptoms of chronic fatigue

syndrome?
The onset of chronic fatigue syndrome symptoms can be fairly sudden
(over a few days or so), or more gradual. Chronic fatigue syndrome should
be suspected if the following symptoms are not explained by any other
condition, and persist for a minimum of six weeks in adults, or four weeks in
children and young people:

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 Extreme tiredness (fatigue) that is worsened by activity, but is not
caused by excessive exertion and is not significantly relieved by rest.

Post-exertional malaise (PEM): feeling unwell with no energy after

activities, with a worsening of symptoms that:

Often doesn't start until hours or days after the activity.

Is much greater than expected for that particular activity.

Has a prolonged recovery time that may last hours, days, weeks
or longer.

Unrefreshing sleep problems or sleep disturbance, which may

include:

Feeling exhausted, feeling flu-like and stiff on waking.

Broken or shallow sleep, altered sleep pattern or excessive

daytime sleepiness (hypersomnia).

Difficulties with conscious physical or mental activities, such as

thinking, reasoning, or remembering (cognitive difficulties),
sometimes described as 'brain fog'. This may include:

Problems finding words or numbers.

Difficulty in speaking.

Slow to respond.

Short-term memory problems.

Difficulty concentrating or multitasking.

Inability to engage fully in work, educational, social or personal

activities is a common symptom.

The diagnosis can only be confirmed after three months of persistent long-
term symptoms and only if the symptoms cannot be explained by any
other condition.

Other chronic fatigue syndrome symptoms

Other symptoms that may be associated with CFS include:

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 Dizziness, palpitations, fainting, nausea on standing or sitting upright
from a lying position.

Increased sensitivity to temperature, causing increased sweating,

chills, hot flushes or feeling very cold.

Flu-like symptoms, including sore throat, tender glands, nausea,

chills or muscle aches.

Intolerance to alcohol, or to certain foods or chemicals.

Increased sensitivities, including to light, sound, touch, taste and

smell.

Pain, including pain on touch, muscle pain, headaches, eye pain,

tummy (abdominal) pain, or joint pain.

Severity of chronic fatigue syndrome

symptoms
Symptoms vary widely in severity and people may have some symptoms
more severely than others. However, the following definitions are provided
by NICE to provide a guide to the level of impact of symptoms on everyday
functioning:

Mild chronic fatigue syndrome

Able to care for oneself and do some light domestic tasks

(sometimes needing support) but may have difficulties with mobility.

Able to work or attend education but to do this have probably

stopped all leisure and social pursuits.

Often have reduced hours, take days off and use the weekend to
cope with the rest of the week.

Moderate chronic fatigue syndrome

Reduced mobility and restrictions in all activities of daily living.

May have peaks and troughs in level of symptoms and ability to do

activities.

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 Have usually stopped work or education and need rest periods, often
resting in the afternoon for one or two hours.

Sleep at night is generally of poor quality and disturbed.

Severe chronic fatigue syndrome

Unable to do any activity for oneself, or can carry out minimal daily
tasks only (such as face washing or cleaning teeth).

Severe cognitive difficulties and may depend on a wheelchair for

mobility.

Often unable to leave the house or have a severe and prolonged

after-effect if you do so.

May also spend most of the time in bed and often extremely sensitive
to light and sound.

Very severe chronic fatigue syndrome

In bed all day and dependent on care.

Need help with personal hygiene and eating and are very sensitive to
sensory stimuli.

Some people with very severe CSF may not be able to swallow and
may need to be tube fed.

How is chronic fatigue syndrome diagnosed?

There is currently no test to aid diagnosis of CFS and it is recognised from
symptoms alone. However, some tests are usually done to rule out other
causes of tiredness or other symptoms.

For example, blood tests may be done to rule out any other medical
conditions such as anaemia, an underactive thyroid gland, liver problems
and kidney problems.

What causes chronic fatigue syndrome?

The cause of chronic fatigue syndrome is not known. There are various
theories but none has been proved.

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A popular theory is that a viral infection may trigger the condition. Tiredness
(fatigue) is a common symptom that can persist for a short time following
certain viral infections. For example, infection with the glandular fever virus
or the influenza virus can cause fatigue for several weeks after other
symptoms have gone. However, most people recover within a few weeks
from the tiredness that follows known viral infections.

Even if a viral infection is a trigger of CFS, it is not clear why symptoms

persist when there is no evidence of persisting infection. Also, many people
with CFS do not have an initial viral infection.

Factors that are thought to contribute to some people developing CFS

include:

Inherited genetic susceptibility (it is more common in some families).

Mental stress.

Depression.

A traumatic event such as bereavement, divorce or redundancy.

It is hoped that research will clarify the cause (or causes) of CFS in the
future.

Who develops chronic fatigue syndrome?

Chronic fatigue syndrome can affect anyone. It is estimated that CFS
affects an average of between one and five people in every 1,000 in the UK.
The true figure may be higher because some people with CFS are not
diagnosed.

It is about three times as common in women as in men. The most common

age for it to develop sometime between the early twenties and mid-forties.
In children the most common age for it to develop is 13-15 years but it can
develop at an earlier age.

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Treating chronic fatigue syndrome
There is no known cure for chronic fatigue syndrome although symptoms
can be self-managed with support and advice. When CFS is suspected, a
diagnosis will be made by a specialist CFS clinic which will also give
individual advice about managing the symptoms. This medical advice will
usually include:

Trying to manage daily activities, not using excess energy and not
'pushing through' any symptoms.

Resting as needed. This might mean making changes to a daily

routine, including work, school and other activities.

Maintaining a healthy balanced diet with adequate fluid intake.

Children and young people with symptoms of CFS should be referred to a

paediatrician for further assessment and investigation before referral to a
paediatric chronic fatigue syndrome specialist team to confirm the
diagnosis and develop a care and support plan.

Energy management
Each person has a different and fluctuating energy limit and individuals
tend to be the expert in judging their own limits.

A personalised physical activity or exercise programme should only be

considered if people feel ready to progress their physical activity beyond
their current activities of daily living or would like to include physical activity
or exercise into managing their CFS.

Some people with chronic fatigue syndrome have found that energy
management programmes can make their symptoms better, some people
find it makes no difference and others find them unhelpful.

An energy management plan for chronic fatigue syndrome uses a flexible

approach that is tailored individually so that activity is never automatically
increased but is maintained or adjusted (upwards after a period of stability
or downwards when symptoms are worse). Energy management can take
weeks, months or sometimes even years to reach stabilisation or to
increase tolerance or activity.

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An energy management plan includes all types of activity (mental,
physical, emotional and social) and takes into account the overall level of
activity. It helps people learn to use the amount of energy they have whilst
reducing the risk of post-exertional malaise or worsening symptoms of
chronic fatigue syndrome by exceeding energy limits.

Any activity or exercise programme must be led by the individual, with

support from a healthcare professional in an CFS specialist team. A
physical activity or exercise programme should be overseen by a
physiotherapist in an CFS specialist team.

The first step is to agree a sustainable level of activity, which may mean
initially reducing activity. This plan should include periods of rest and
activity. It is important to alternate and vary between different types of
activity and to break activities into small chunks.

Exercise that is not part of the programme, such as going to the gym,
should be avoided because this may worsen symptoms. Graded exercise
therapy in which you make fixed increases in the time spent being
physically active is no longer recommended in CFS.

Cognitive behavioural therapy

Cognitive behavioural therapy (CBT) can be offered to help people
manage their symptoms, improve their level of functioning and reduce the
distress associated with having a chronic illness.

CBT for people with CFS aims to improve quality of life.

CBT should aim to help people develop an understanding about the main
difficulties and challenges they face, explore their understanding of their
symptoms and illness and so help to manage symptoms.

Severe or very severe CFS/ME

People with severe or very severe CFS/ME will need more frequent reviews
and increased support and care. They should also be referred:

To a physiotherapist or occupational therapist working in an CFS

specialist team for support on developing energy management
plans.

To a dietician with a special interest in CFS.

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The process and pace of any CBT should be adjusted to meet their needs.
This might include shorter, less frequent sessions and longer-term goals.

Flare-ups and relapse of chronic fatigue syndrome

Flare-ups and relapses can happen even if the symptoms are generally
well-managed. It is very important that people are given and agree
individual advice on how to adjust their activity during a flare-up or relapse.
This should include how to access review and support from a
physiotherapist in an CFS specialist team. The time it takes to return to the
previous level of physical activity varies from person to person.

Flare-up

These usually last a few days and is a worsening of the symptoms beyond
the normal day-to-day variation. Some flare-ups will develop into a
relapse. For a flare-up:

It is useful to identify possible triggers, such as acute illness or

overexertion, but there may be no clear trigger.

It is best to temporarily reduce activity levels, monitor symptoms and

avoid returning to usual activity levels until the flare-up has resolved.

Relapse

This is a more persistent and marked increase in symptoms, needing a

substantial and sustained adjustment of energy management. For a
relapse:

It is useful to identify possible causes.

It is best to reduce or stop some activities.

It is important to increase the frequency or duration of rest periods.

It is necessary to reassess energy limits to help stabilise the

symptoms.

Ideally there should be a named contact in the CFS specialist team who
can advise if the flare-up or relapse cannot be managed with planned self-
management strategies.

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How to help chronic fatigue syndrome
Rest and sleep
Rest periods in the daily routine are part of management strategies for all
people with chronic fatigue syndrome.

Relaxation techniques at the beginning of each rest period can be helpful. It

is important to balance the need for rest during the day against the need
for sleep at night. Any changes to sleep pattern should be introduced
gradually.

Physical functioning and mobility

Strategies to help maintain and prevent deterioration of physical function
and mobility need to be carried out in small amounts spread out
throughout the day.

Strategies should focus on joint mobility, muscle flexibility, balance, postural

and positional support, muscle function, bone health and cardiovascular
health.

Care and support plans in relation to physical functioning and mobility may
include bed mobility, moving from lying to sitting to standing, transferring
from bed to chair, using mobility aids, walking, joint mobility, muscle
stretching, muscle strength, balance, and going up and down stairs.

People with CFS may experience intolerance of changing position, such as

when first standing up. This may include postural orthostatic tachycardia
syndrome (PoTS). A specialist referral may be needed if the symptoms are
severe or worsening or if there are concerns that another condition may be
the cause.

Dealing with pain

Chronic pain is commonly associated with CFS. Referral to specialist pain
services may be needed.

Medicines
People with chronic fatigue syndrome may be more intolerant of drug
treatment. Therefore, medicines might need to be started at a lower dose
than usual and then gradually increased.

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Dietary management and strategies
Adequate fluid intake and a well-balanced diet are essential. A dietician
with a special interest in CFS might be involved if someone is:

Losing weight and at risk of malnutrition.

Gaining weight.

Following a restrictive diet.

Children and young people with CFS who are losing weight, have poor
growth or have a restricted diet should be assessed by a paediatric
dietician with a special interest in CFS.

People with CFS may be at risk of vitamin D deficiency, especially those who
are housebound or bed-bound.

There is not enough evidence to support routinely taking vitamin and

mineral supplements as a cure for CFS or for managing symptoms.

Review of CFS in primary care

Adults with CFS should be seen for a review of their care and support plan
in primary care at least once a year. Children and young people with CFS
should have a review of their care and support plan at least every six
months. These should be carried out or overseen by a paediatrician with
expertise in CFS.

What is the outlook (prognosis)?

The long-term outlook for chronic fatigue syndrome varies from person to
person. Although some people recover or have a long period of remission,
many will need to adapt to living with CFS.

The outlook is better in children and young people than in adults. Chronic
fatigue syndrome affects everyone differently and its impact varies widely.

For most people, symptoms still allow them to carry out some activities,
whereas for others they cause severe impacts.

Further reading
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 Myalgic encephalomyelitis (or encephalopathy)/chronic fatigue syndrome:
diagnosis and management; NICE guideline (October 2021)
Cortes Rivera M, Mastronardi C, Silva-Aldana CT, et al; Myalgic
Encephalomyelitis/Chronic Fatigue Syndrome: A Comprehensive Review.
Diagnostics (Basel). 2019 Aug 7;9(3). pii: diagnostics9030091. doi:
10.3390/diagnostics9030091.
Kim DY, Lee JS, Park SY, et al; Systematic review of randomized controlled trials
for chronic fatigue syndrome/myalgic encephalomyelitis (CFS/ME). J Transl
Med. 2020 Jan 6;18(1):7. doi: 10.1186/s12967-019-02196-9.
Collard SS, Murphy J; Management of chronic fatigue syndrome/myalgic
encephalomyelitis in a pediatric population: A scoping review. J Child Health
Care. 2020 Sep;24(3):411-431. doi: 10.1177/1367493519864747. Epub 2019 Aug 4.

Disclaimer: This article is for information only and should not be used for the
diagnosis or treatment of medical conditions. Egton Medical Information Systems
Limited has used all reasonable care in compiling the information but makes no
warranty as to its accuracy. Consult a doctor or other healthcare professional for
diagnosis and treatment of medical conditions. For details see our conditions.

Authored by: Peer Reviewed by:

Dr Surangi Mendis

Originally Published: Next review date: Document ID:

19/11/2023 21/08/2023 doc_4859

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