Topic Overview

What is myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS)?

Myalgic encephalomyelitis/chronic
fatigue syndrome (ME/CFS) (say “my-AL-jik en-seh-fuh-loh-my-uh-LY-tus”) is a condition that makes you feel so
tired that you can’t do all of your normal, daily activities. There are other
symptoms too, but being very tired is the main
one. Some people have severe fatigue and other symptoms for
many years. Another name for this condition is systemic exertion intolerance disease.

ME/CFS is not well understood. Most experts now
believe that it is a separate illness with its own set of symptoms. But some
doctors don’t believe this.

There are no tests for ME/CFS. Because
of this, many people have trouble accepting their disease or getting their
friends and family to do so. Having people who believe your diagnosis and
support you is very important. Having a doctor you can trust is critical.

Your tiredness is real. It’s not “in your head.” It is your
body’s reaction to a mix of factors.

What causes ME/CFS?

Doctors don’t know what causes
ME/CFS. Sometimes it begins after a viral infection, but there is no proof
of any connection. It’s likely that a number of factors or triggers come
together to cause ME/CFS.

What are the symptoms?

Extreme tiredness, or
fatigue, is the main symptom. If you have ME/CFS:

  • You may feel exhausted all or much of the
  • You may have problems sleeping. Or you may wake up feeling
    tired or not rested.
  • It may be harder for you to think clearly, to
    concentrate, and to remember things.
  • You may also have headaches,
    muscle and joint pain, a sore throat, and tender glands in your neck or
  • Your symptoms may flare up after a mental or physical
    activity that used to be no problem for you. You may feel drained or exhausted.

Depression is common with ME/CFS, and it can make your other
symptoms worse.

How is ME/CFS diagnosed?

There are no tests for ME/CFS.
Doctors may also look for other causes of your fatigue. Many other health problems can cause fatigue. Most people with
fatigue have something other than ME/CFS.

Here is one set of criteria (rules) that doctors use to diagnose ME/CFS:footnote 1

  • The fatigue and the other symptoms must last, or come and go, for at least 6 months.
  • The symptoms cannot be explained by another illness.
  • All of these symptoms must be present:
    • Extreme physical or mental fatigue that affects how well you can take part in work, school, social, or personal activities
    • Not feeling well after being active (post-exertional malaise)
    • Sleep problems
  • One or more of these symptoms must be present:
    • Problems with concentration, short-term memory, or thinking of the right word (cognitive impairment)
    • Feeling dizzy or faint while standing that improves while lying down (orthostatic intolerance)
  • Symptoms of ME/CFS should be moderate to severe and present at least 3 months.

How is it treated?

There is no treatment for ME/CFS
itself, but many of its symptoms can be treated. A good relationship with your
doctor is important. That’s because the two of you will need to work together to find
a combination of medicines and behavior changes that will help you get better.
Some trial and error may be needed, because no single combination of
treatments works for everyone.

Home treatment is very important.
You may need to change your daily schedule, learn better sleep habits, and
use regular gentle movement or exercise to fight fatigue. Even at times when you have more energy, keep a low-key pace throughout each day. Rest often.

Living with ME/CFS can be as much a mental health challenge as it is a physical one. Take steps to avoid getting caught
in a cycle of frustration, anger, and depression. Learning to cope with your
symptoms and talking to others who have ME/CFS can help. So can working with a counselor.

Frequently Asked Questions

Learning about ME/CFS:

Being diagnosed:

Getting treatment:

Living with ME/CFS:

Health Tools

Health Tools help you make wise health decisions or take action to improve your health.


Doctors don’t know what causes
ME/CFS. For many people, ME/CFS symptoms start after a viral illness. In some cases, ME/CFS seems to follow a major physical or emotional trauma or an exposure to toxins. But there is no single known cause of ME/CFS.

Other theories point to the
immune system, glands and hormones, and family history. But again, there’s not enough evidence to prove
a solid connection.


ME/CFS symptoms usually start suddenly. But for some people, they develop gradually over weeks or months. Symptoms can change in a day, and from day to day. They tend to stop (remission) and then start again (relapse).

There is broad range of ME/CFS symptoms. But there is a core set of symptoms that affect nearly everyone with ME/CFS. These core symptoms are:

  • Extreme physical fatigue, mental fatigue, or both. It can be constant, or it can come and go. It is not relieved by rest. This fatigue also is so severe that it interferes with your
    work, your play, and your social activities.
  • Feeling unwell after being active. This can mean you feel ill or weak or your ME/CFS symptoms are worse. There can be a delay before it starts. It can take more than 24 hours to feel better.
  • Sleep problems.
  • Pain, which can be widespread or in one place. ME/CFS pain can be in one area, then move to another. You may have:
    • Muscle pain.
    • Joint pain.
    • Headache.

A person with ME/CFS may have one or more of these symptoms:

  • Problems with concentration, short-term memory, or thinking of the right word (cognitive impairment)
  • Feeling dizzy or faint while standing that improves while lying down (orthostatic intolerance)

ME/CFS may also cause the following symptoms. Different people with ME/CFS have different combinations of:

  • Lightheadedness and dizziness, very fast heartbeat, or shortness of breath when active.
  • Urinating often, nausea, or irritable bowel syndrome (IBS).
  • Low body temperature, cold hands and feet, sweating, or trouble with heat or cold.
  • Feeling worse when under stress.
  • Weight change or appetite change.

Having depression along with ME/CFS is common and can make ME/CFS symptoms

causes symptoms that are the same as many other diseases, especially early on. For this reason, it can be diagnosed only after a thorough evaluation has ruled
out other conditions with similar symptoms.

What Happens

In some cases,
ME/CFS develops after a flu-like
illness such as
mononucleosis (mono) or after a period of unusual stress. But it may
also occur without warning, even if you have not been sick.

fatigue may come upon you gradually or quite suddenly. Because fatigue can be
vague and can be caused by many things, you might not pay attention to the
problem for several weeks or months. It is hard to say what is normal with ME/CFS. That’s
because the diagnosis often is not clear for some time.


  • Symptoms are worse at the
  • You may feel better for a time and then feel
    worse again. Some people have severe
    fatigue and other symptoms for many years. But many people will feel somewhat better or a lot better over time.

Some people find the fatigue, pain, and thinking problems
caused by ME/CFS greatly hamper their lives. But other people are not nearly as

  • Most people are still able to do some of
    their usual activities at home and work, but they often are unusually tired
    after they do them. People often have to cut down on social and recreational
    activities to save their energy for work and family.
  • Other people
    have trouble doing most or all of their daily activities, including work and
    the basic chores of daily living. They may have to carefully plan how to best
    use their energy.
  • People with severe ME/CFS have trouble getting out of bed and need help with basic activities
    such as dressing, eating, and bathing.

What Increases Your Risk

People who have
ME/CFS are generally 25 to 45
years of age. Women are more likely to have ME/CFS.

ME/CFS is rare in
children. It may occur in teens, especially young teenage girls. Unlike
adults, teens are more likely to develop ME/CFS after having a flu-like illness.

When To Call a Doctor

It’s important to talk to your
doctor about any symptoms you may have.

Call your doctor if
you have:

  • Severe fatigue that lasts longer than 2 weeks,
    causes you to limit your usual activities, and does not improve with
  • Sleep problems that last for more
    than 1 to 2 months. These problems may include being unable to fall asleep or stay asleep,
    tossing and turning, and waking up feeling tired or not rested.
  • Swelling in the glands in your neck or armpits
    (without other signs of infection) that lasts for at least 2 weeks.
  • Severe fatigue along with frequent urination (especially at
    night), extreme thirst, weight loss, or blurred vision. Fatigue that occurs
    with some or all of these may be a symptom of undiagnosed
  • Headache that lasts longer than 2 weeks.

Watchful waiting

Watchful waiting refers to a period of time in which you are being
watched by your doctor but are not getting treatment. A month or two of paying close attention to your
sleep habits, getting regular moderate exercise, trying to control stress, and
eating a balanced diet will take care of most cases of fatigue not caused by
ME/CFS or another medical problem. But if your fatigue has not improved after
1 to 2 months of self-care, or if fatigue won’t go away and limits your usual
activities, call your doctor.

If you have been diagnosed with ME/CFS,
pay attention to any new symptoms and report them to your
doctor. Although ME/CFS can cause a variety of symptoms, new symptoms could be
caused by another illness or medical condition that may need to be evaluated
and treated.

Who to see

The following health professionals can evaluate
fatigue and other symptoms:

There are doctors who specialize in the treatment of ME/CFS.
Get a recommendation from your family doctor or a local ME/CFS support group
before you make an appointment with a specialist. It is always wise to start with
your family doctor. You may also be referred to a physiatrist, psychologist, or

To prepare for your appointment, see the topic Making the Most of Your Appointment.

Exams and Tests

ME/CFS is hard to diagnose. It is common to have normal test results when you have ME/CFS. Fatigue is an extremely common
problem, and it can have many other causes.

First, your doctor will ask you about past health and do a physical exam. Experts have
come up with a specific list of symptoms to decide whether a person has ME/CFS.
Doctors use a variety of tests to rule out other conditions. These tests
usually include:

These are routine lab tests. Other tests may be done if
your symptoms, history, and physical exam suggest other possible problems.
These other tests may include:

Some doctors may order tests that check your
immune system. These can be expensive and generally
are done only in research settings. Also, it’s hard to know what the
findings of these tests mean. That’s because so little is known about the immune
system’s connection to ME/CFS.

Treatment Overview

Since there is not yet a cure for ME/CFS, the key to living with ME/CFS is treating your symptoms.

  • Find a primary doctor who understands ME/CFS and how to treat it, and who helps you feel supported.
  • Track what helps you feel better, as well as the things that make your symptoms worse.
  • Use a mix of medical care, daily self-care, and support.
  • For regular support you can count on, work with a professional counselor, a ME/CFS support group, or both.
  • Get specialist care when you need it. Sign “release of information” forms so that your doctors can work together as a team.

Treat the worst first

Start by listing your worst symptoms-the ones that make it hardest to get through the day. With your doctor, focus first on treating those symptoms. Decide whether a specialist might be helpful for any of them.

The most common ME/CFS symptoms can also be the most treatable.


Good sleep habits can help improve the quality of your sleep. If you also try medicine for sleep, it’s best to start on a low dose. Certain antidepressants help with sleep, mood, and chronic pain, so your doctor may suggest trying one.


Different kinds of pain can be treated in different ways. If one treatment doesn’t work, you and your doctor can try another until you find what works best for you.

  • It’s important to control focused pain, such as arthritis or migraine, because this kind of pain can make ME/CFS body pain worse. First try an over-the-counter pain reliever, like acetaminophen (such as Tylenol), ibuprofen (such as
    Advil or Motrin), or naproxen (such as Aleve). Be safe with medicines. Read and follow all instructions on the label.
  • There are different types of prescription medicines that help with pain, such as antidepressants or anticonvulsants for chronic pain and opioid
    medicine for severe pain.
  • Other treatments that can help with ME/CFS pain include acupuncture, massage, or yoga.


Do all you can to take charge of your fatigue level. Even when you have more energy, keep a low-key pace throughout each day.

Your doctor may recommend a program like graded exercise or cognitive-behavioral therapy as part of your treatment plan. More research is needed to better understand how well these treatments work for ME/CFS.

Depression, anxiety, and distress

Living with ME/CFS can be as much a mental health challenge as it is a physical one. It’s easy to get caught
in a cycle of frustration, anger, and depression.

  • Work with your doctor to watch for signs of depression. It can be easy to mistake depression for ME/CFS fatigue.
  • If your doctor suggests an antidepressant, ask if there is one that may not only improve
    your mood, but also help control your pain and help you sleep.
  • For support and help with mood problems, you can also work with a professional counselor who understands ME/CFS.

Get specialist care when you need it

You can expect your symptoms to come and go. For some people, certain things trigger long periods of worse symptoms. Visit your doctor every few months to help
track your symptoms and check for any need to change your treatment.

Get specialized care if you need it. For example:

  • A rehabilitation specialist can help you start a graded exercise plan. He or she can also treat pain.
  • A pain management specialist can offer a number of pain treatments.
  • There are some specialists who work with experimental treatments such as antiviral medicines.

What to think about

There are many
unproven remedies, such as special diets or mineral
supplements, that some people recommend for treating ME/CFS. There is no evidence
that any of these are effective.

Your mind and body are connected and affect each other. Physical illnesses
can be made worse-or better-by your feelings and attitudes, and vice versa. Learn as much as you can about ME/CFS. Then work with your doctor to learn
ways to cope with your symptoms. Get emotional support from your health
professionals as well as from your family and friends.


ME/CFS can’t be prevented or cured. But treatment can help control or reduce symptoms.

Home Treatment

Home treatment is the most important
part of treating
can take steps to control and sometimes relieve your ME/CFS symptoms:

  • Adjust your schedule to take advantage
    of times when you have more energy and feel less tired. Keep a diary for a week
    or so. Write down the times of day when you have energy and when you are tired.
    If there is a pattern to how your energy level changes during the day, try to
    plan your work, school, or other activities around that
  • Do what you can to take charge of your fatigue level. Try not to do too much when you have more energy. If
    you do too much, you may become overtired. And it may take several days for you
    to recover.
  • Improve your sleep habits. Sleep problems may
    add to your fatigue and other symptoms.

    • Go to bed only when you are sleepy. Get
      up at the same time every day, whether or not you feel rested.
    • If you lie awake for longer than 15 minutes, get up, leave the
      bedroom, and do something quiet until you feel sleepy again.
    • Avoid
      alcohol, caffeine, and tobacco well before bed. Alcohol can disrupt your sleep when you drink it within 4 hours of bedtime. Caffeine is a stimulant that stays in the body for 12 hours. So make sure to avoid it during that block of hours before your bedtime.
    • Keep the bedroom at a
      comfortable temperature. Get rid of all sound and light disturbances.
    • Make sure your mattress provides good support. Use a neck support
      pillow to keep your head and neck from moving too much when you
    • Take naps if you need to. Keep them short (20 to 60
      minutes). And try not to take them late in the day or evening.
  • Try getting light, gentle exercise regularly. Stretching
    is a good start. Light aerobic exercise such as walking, swimming,
    or riding a bicycle or stationary bike can also be helpful. Try to keep a
    balance between being active enough to benefit from it and exercising so much
    that you become overtired.

  • Try taking nonprescription pain medicines to
    relieve muscle and joint pain and headaches caused by ME/CFS. Medicines that may
    be helpful include acetaminophen (such as Tylenol), ibuprofen (such as
    Advil or Motrin), and naproxen (such as Aleve). Be safe with medicines. Read and follow all instructions on the label. Talk to your doctor if your pain is not relieved by nonprescription medicine.
  • Join a support group. These groups can be a good source of information and tips
    for managing your illness. They also give you a chance to share your frustrations and
    problems with others who have ME/CFS. Ask your doctor or contact a local hospital
    for the location of a support group near you.
  • Eat a balanced diet. Include plenty of fruits, vegetables, grains, cereals, legumes, poultry, fish, lean meats, and low-fat dairy products.

Try to be patient. Keep in mind that daily home treatment
usually helps relieve or control ME/CFS symptoms. Your doctor may suggest
cognitive-behavioral therapy to help you with your home treatment.


Medicines do not cure
ME/CFS. But they can help relieve
your symptoms.

Medicine choices

Over-the-counter medicines include:

  • Pain relievers and anti-inflammatory drugs: Over-the-counter drugs include acetaminophen (for
    example, Tylenol), ibuprofen (for example, Advil, Motrin), and naproxen (for example, Aleve). They sometimes relieve frequent or severe joint and
    muscle pain, headaches, and fevers. Be safe with medicines. Read and follow all instructions on the label. Talk to your doctor if your pain is not relieved by nonprescription medicine.

Prescription medicines include:

  • Anticonvulsants, also called antiseizure medicines. This type of drug, such as gabapentin and pregabalin, is sometimes prescribed for pain and sleep problems. It seems to work best when used for nerve pain.
  • Antidepressants.
    Antidepressant medicine is prescribed by a doctor to ease depression and anxiety,
    improve your ability to concentrate, and help you sleep better.

For more information about treating some types of pain that may occur with ME/CFS, see:

What to think about

Some research has studied the
use of
corticosteroids (such as hydrocortisone and
fludrocortisone) to treat ME/CFS. Studies have shown
that these medicines don’t work very well to treat ME/CFS. And the side effects
can be serious. Unless corticosteroids can be shown to have a greater benefit
for people with ME/CFS over a longer period of time, the side effects associated
with long-term corticosteroid therapy outweigh the benefits from their use in
most cases.footnote 3

Depression often becomes a part of
ME/CFS and can make your symptoms worse. Like any medical
illness, depression needs to be treated. If you have ME/CFS and feel depressed,
talk to your doctor and get treatment.

Other Treatment

The best treatment for your ME/CFS is what makes you feel better. Along with daily self-care and the treatment you get from your doctor, you might find that other treatments help too.

There are safe nontraditional
treatments that can relieve
pain and stress, ease muscle tension, help you feel better and healthier, and
improve your outlook and quality of life.

Treatment choices

Some popular complementary treatments include:

Unproven treatments

There are many unproven treatments for ME/CFS. Some of the more popular ones include:

  • Large doses of vitamins or minerals. But taking too much of certain vitamins and minerals can
    actually be harmful.
  • Diets that eliminate certain foods or
    ingredients (such as yeast, sugar, or food additives) that some people believe
    stress the
    immune system. Because the exact role of the immune
    system in ME/CFS isn’t well understood, there is no scientific basis for these
    remedies. But if certain foods seem to make your symptoms worse, there is
    no harm in avoiding them as long as you are eating a balanced diet.
  • Aloe vera juice.
  • Evening primrose oil.
  • Royal jelly (a bee product).

What to think about

None of these complementary
treatments have been proven effective in treating ME/CFS, but some people have
reported feeling better after using them. If you have ME/CFS and are thinking
about trying a complementary treatment, get the facts before you begin. Consider
these questions with your doctor:

  • Is it safe? Do not use
    treatments that could harm you, such as unusual diets or excessive vitamin or
    mineral supplements. (A daily multiple vitamin is okay. Try to avoid taking
    more than 100% of the
    recommended daily allowance for any vitamin or mineral
    unless your doctor prescribes it.)
  • Is the product manufactured reliably? Vitamin and mineral supplements and herbal
    products are not subject to the same regulations as medicines. Ingredients may
    vary from one maker to another. Read the labels carefully, and choose well-known
    brands you trust.
  • Does it work? It may be
    hard to tell whether a treatment is working. Keep in mind that when you get
    better after treatment, the treatment may not be the reason for your
    improvement. Symptoms of ME/CFS often improve on their own. Or the treatment may
    be causing a
    placebo effect, which makes you feel
  • How much does it cost? An expensive
    treatment that may or may not help you may not be worth the high cost. Beware
    of products or treatment providers who require a large financial investment up
    front or a series of costly treatments.
  • Will it improve my general health? Even if complementary treatments are not
    effective in treating ME/CFS, some of them are safe and healthy habits that may
    improve your general well-being and may be worth trying.

Avoid products that claim to have a “secret” ingredient or that claim
to cure ME/CFS. Currently, there is no cure for ME/CFS. Any benefit reported as a
result of using a product is most likely due to improved symptom management,
chance, or, possibly, the illness running its course.

For more information, see the topic
Complementary Medicine.

Other Places To Get Help


Centers for Disease Control and Prevention: Chronic Fatigue Syndrome (U.S.)

Chronic Fatigue and Immune Dysfunction Syndrome (CFIDS)
Association of America



  1. Institute of Medicine (2015). Beyond myalgic encephalomyelitis/chronic fatigue syndrome: Redefining an illness. Institute of Medicine. Accessed January 31, 2017.
  2. Brurberg L, et al. (2015). Exercise as treatment for patients with chronic fatigue syndrome. Cochrane Database of Systematic Reviews (2). Accessed February 23, 2016.
  3. Cleare A, et al. (2015). Chronic fatigue syndrome. BMJ Clinical Evidence, published online September 28, 2015. Accessed February 23, 2016.

Other Works Consulted

  • Agency for Healthcare Research and Quality (2014). Diagnosis and treatment of myalgic encephalomyelitis/chronic fatigue syndrome (Evidence Report/Technology Assessment No. 219). Rockville, MD: Agency for Healthcare Research and Quality. Accessed February 23, 2016.
  • Bleijenberg G, ven der Meer JWM (2015). Chronic fatigue syndrome. In DL Kasper et al., eds., Harrison’s Principles of Internal Medicine, 19th ed., CD chap. 464e. New York: McGraw-Hill Education.
  • International Association for Chronic Fatigue Syndrome/Myalgic Encephalomyelitis (2014). Chronic fatigue syndrome myalgic encephalomyelitis: A primer for clinical practitioners. Chicago, IL: IACFS/ME. Accessed February 23, 2016.
  • Sharpe M, et al. (2015). Rehabilitative treatments for chronic fatigue syndrome: Long-term follow-up from the PACE trial. Lancet Psychiatry, 2(12): 1067-1074. DOI: 10.1016/S2215-0366(15)00317-X. Accessed February 26, 2016.


ByHealthwise Staff
Primary Medical Reviewer Anne C. Poinier, MD – Internal Medicine
E. Gregory Thompson, MD – Internal Medicine
Adam Husney, MD – Family Medicine
Kathleen Romito, MD – Family Medicine
Specialist Medical Reviewer Martin J. Gabica, MD – Family Medicine

Current as ofOctober 9, 2017