Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a disabling and complex illness.

People with ME/CFS are often not able to do their usual activities. At times, ME/CFS may confine them to bed. People with ME/CFS have overwhelming fatigue that is not improved by rest. ME/CFS may get worse after any activity, whether it’s physical or mental. This symptom is known as post-exertional malaise (PEM). Other symptoms can include problems with sleep, thinking and concentrating, pain, and dizziness. People with ME/CFS may not look ill. However,

• People with ME/CFS are not able to function the same way they did before they became ill.
• ME/CFS changes people’s ability to do daily tasks, like taking a shower or preparing a meal.
• ME/CFS often makes it hard to keep a job, go to school, and take part in family and social life.
• ME/CFS can last for years and sometimes leads to serious disability.
• At least one in four ME/CFS patients is bed- or house-bound for long periods during their illness.

Anyone can get ME/CFS. While most common in people between 40 and 60 years old, the illness affects children, adolescents, and adults of all ages. Among adults, women are affected more often than men. White persons are diagnosed more than other races and ethnicities. But many people with ME/CFS have not been diagnosed, especially among people from racial and ethnic minority groups.

As noted in the IOM report:

• An estimated 836,000 to 2.5 million Americans suffer from ME/CFS.
• About 90 percent of people with ME/CFS have not been diagnosed.
• ME/CFS costs the U.S. economy about $17 to $24 billion annually in medical bills and lost incomes.

Some of the reasons that people with ME/CFS have not been diagnosed include limited access to healthcare and a lack of education about ME/CFS among healthcare providers.

• Most medical schools in the United States do not have ME/CFS as part of their physician training.
• The illness is often misunderstood and might not be taken seriously by some healthcare providers.
• More education for doctors and nurses is urgently needed so they are prepared to provide timely diagnosis and appropriate care for patients.

Researchers have not yet found what causes ME/CFS, and there are no specific laboratory tests to diagnose ME/CFS directly. Therefore, doctors need to consider the diagnosis of ME/CFS based on in-depth evaluation of a person’s symptoms and medical history. It is also important that doctors diagnose and treat any other conditions that can cause similar symptoms. Even though there is no cure for ME/CFS, some symptoms can be treated or managed.

What is chronic fatigue syndrome?

Chronic fatigue syndrome (CFS) is a serious, long-term illness that affects many body systems. Another name for it is myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS). CFS can often make you unable to do your usual activities. Sometimes you may not even be able to get out of bed.

What causes chronic fatigue syndrome?

The cause of CFS is unknown. There may be more than one thing that causes it. It is possible that two or more triggers might work together to cause the illness.

Who is at risk for chronic fatigue syndrome?

Anyone can get CFS, but it is most common in people between 40 and 60 years old. Adult women have it more often that adult men. Whites are more likely than other races to get a diagnosis of CFS, but many people with CFS have not been diagnosed with it.

What are the symptoms of chronic fatigue syndrome?

CFS symptoms can include

• Severe fatigue that is not improved by rest
• Sleep problems
• Post-exertional malaise (PEM), where your symptoms get worse after any physical or mental activity
• Problems with thinking and concentrating
• Pain
• Dizziness

CFS can be unpredictable. Your symptoms may come and go. They may change over time - sometimes they might get better, and other times they may get worse.

How is chronic fatigue syndrome diagnosed?

CFS can be difficult to diagnose. There is no specific test for CFS, and other illnesses can cause similar symptoms. Your health care provider has to rule out other diseases before making a diagnosis of CFS. He or she will do a thorough medical exam, including

• Asking about your medical history and your family's medical history
• Asking about your current illness, including your symptoms. Your doctor will want to know how often you have symptoms, how bad they are, how long they have lasted, and how they affect your life.
• A thorough physical and mental status exam
• Blood, urine or other tests

What are the treatments for chronic fatigue syndrome?

There is no cure or approved treatment for CFS, but you may be able to treat or manage some of your symptoms. You, your family, and your health care provider should work together to decide on a plan. You should figure out which symptom causes the most problems and try to treat that first. For example, if sleep problems affect you the most, you might first try using good sleep habits. If those do not help, you may need to take medicines or see a sleep specialist.

Strategies such as learning new ways to manage activity can also be helpful. You need to make sure that you do not "push and crash." This can happen when you feel better, do too much, and then get worse again.

Since the process of developing a treatment plan and attending to self-care can be hard if you have CFS, it is important to have support from family members and friends.

Don't try any new treatments without talking to your health care provider. Some treatments that are promoted as cures for CFS are unproven, often costly, and could be dangerous.

Scientists have not yet identified what causes myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS). It is possible that ME/CFS has more than one cause, meaning that patients with ME/CFS could have illness resulting from different causes (see below). In addition, it is possible that two or more triggers might work together to cause the illness.

Some of the areas that are being studied as possible causes of ME/CFS are:

Infections

People with ME/CFS often have their illness begin in a way that reminds them of getting the flu. This has made researchers suspect an infection may trigger ME/CFS. In addition, about one in ten people who become infected with Epstein-Barr virus, Ross River virus, or Coxiella burnetti will develop a set of symptoms that meet the criteria for ME/CFS. People with these infections who had severe symptoms are more likely than those with mild symptoms to later develop ME/CFS symptoms. But not all people with ME/CFS have had these infections.

Other infections that have been studied in connection with ME/CFS are human herpesvirus 6, enterovirus, rubella, Candida albicans, bornaviruses, mycoplasma, and human immunodeficiency virus (HIV). However, these infections have not been found to cause ME/CFS.

Immune System Changes

It is possible that ME/CFS is caused by a change in the person’s immune system and the way it responds to infection or stress. ME/CFS shares some features of autoimmune illnesses (diseases in which the immune system attacks healthy tissues in own body, like in rheumatoid arthritis). For example, both ME/CFS and most autoimmune diseases are more common in women and both are characterized by increased inflammation. However, other signs of autoimmune disease, like tissue damage, are not found in patients with ME/CFS.

Scientists think that the immune system might be contributing to ME/CFS in other ways, including:

• Chronic production of cytokines (cytokines are proteins that are produced by the immune system and regulate behavior of other cells). Higher levels of cytokines for a prolonged period can lead to changes in the body’s ability to respond to stress and might lead to the development of health conditions, including ME/CFS.
• Low-functioning natural killer (NK) cells. NK cells are cells of the immune system that help the body fight infections. Many patients with ME/CFS have NK cells with lower functional ability to fight infections. Studies have found that the poorer the function of NK cells in ME/CFS patients, the worse the severity of the illness. NK cell function tests are hard to do and their results are not reliable outside of research studies. Because of this problem, NK cell function testing is not yet useful for healthcare providers. Also, low NK cell function can occur in other illnesses and thus cannot be used to diagnose ME/CFS.
• Differences in markers of T-cell activation. T-cells are cells of the immune system that help activate and suppress immune responses to infections. If they become too active or not active enough, the immune response does not work as it should. However, not all patients with ME/CFS appear to have these differences in markers of T-cell activation.

Stress Affecting Body Chemistry

Physical or emotional stress affects the hypothalamic-pituitary-adrenal axis (HPA axis). The HPA axis is a complex network that controls our body’s reaction to stress and regulates a lot of body processes such as the immune response, digestion, energy usage, and mood. This occurs through connections between two glands of the nervous system (hypothalamus and pituitary) and adrenal glands (small organs that reside on top of the kidneys). The glands release various hormones, like corticotrophin-releasing hormone (CRH), cortisol, and others. When these hormones get out of balance, many body systems and functions, like the immune response, can be negatively affected. Cortisol, also called “the stress hormone,” helps to lower inflammation and calm down the immune system. Low levels of cortisol thus may lead to an increase in inflammation and chronic activation of the immune system.

Patients with ME/CFS commonly report physical or emotional stress before they become ill. Some patients with ME/CFS have lower levels of cortisol than healthy people, but their cortisol levels are still within the normal range. Therefore, doctors cannot use cortisol levels to diagnose or treat ME/CFS.

Changes in Energy Production

Scientists found differences between people with ME/CFS and healthy people in the way cells in their bodies get their energy. However, more studies are needed to figure out how these findings may be contributing to the illness.

Possible Genetic Link

Members of the same family sometimes have ME/CFS. Studies done in twins and families suggest that both genes and environment might play a role in ME/CFS. Scientists have not yet found the exact genes or other factors from the environment that may be responsible. More research is needed.

Primary Symptoms

Also called “core” symptoms, three primary symptoms are required for diagnosis:

• Greatly lowered ability to do activities that were usual before the illness. This drop in activity level occurs along with fatigue and must last six months or longer. People with ME/CFS have fatigue that is very different from just being tired. The fatigue of ME/CFS:
  • Can be severe.
  • Is not a result of unusually difficult activity.
  • Is not relieved by sleep or rest.
  • Was not a problem before becoming ill (not life-long).
• Worsening of ME/CFS symptoms after physical or mental activity that would not have caused a problem before illness. This is known as post-exertional malaise (PEM). People with ME/CFS often describe this experience as a “crash,” “relapse,” or “collapse.” During PEM, any ME/CFS symptoms may get worse or first appear, including difficulty thinking, problems sleeping, sore throat, headaches, feeling dizzy, or severe tiredness. It may take days, weeks, or longer to recover from a crash. Sometimes patients may be house-bound or even completely bed-bound during crashes. People with ME/CFS may not be able to predict what will cause a crash or how long it will last. As examples:
  • Attending a child’s school event may leave someone house-bound for a couple of days and not able to do needed tasks, like laundry.
  • Shopping at the grocery store may cause a physical crash that requires a nap in the car before driving home or a call for a ride home.
  • Taking a shower may leave someone with ME/CFS bed-bound and unable to do anything for days.
  • Keeping up with work may lead to spending evenings and weekends recovering from the effort.

• Sleep problems. People with ME/CFS may not feel better or less tired, even after a full night of sleep. Some people with ME/CFS may have problems falling asleep or staying asleep.

In addition to these core symptoms, one of the following two symptoms is required for diagnosis:

• Problems with thinking and memory. Most people with ME/CFS have trouble thinking quickly, remembering things, and paying attention to details. Patients often say they have “brain fog” to describe this problem because they feel “stuck in a fog” and not able to think clearly.
• Worsening of symptoms while standing or sitting upright.This is calledorthostatic intolerance. People with ME/CFS may be lightheaded, dizzy, weak, or faint while standing or sitting up. They may have vision changes like blurring or seeing spots.

Other Common Symptoms

Many but not all people with ME/CFS have other symptoms.

Pain is very common in people with ME/CFS. The type of pain, where it occurs, and how bad it is varies a lot. The pain people with ME/CFS feel is not caused by an injury. The most common types of pain in ME/CFS are:

• Muscle pain and aches
• Joint pain without swelling or redness
• Headaches, either new or worsening

Some people with ME/CFS may also have:

• Tender lymph nodes in the neck or armpits
• A sore throat that happens often
• Digestive issues, like irritable bowel syndrome
• Chills and night sweats
• Allergies and sensitivities to foods, odors, chemicals, light, or noise
• Muscle weakness
• Shortness of breath
• Irregular heartbeat

To diagnose myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS), a patient’s doctor or healthcare provider will:

• Ask about medical history of the patient and their family

• Do a thorough physical and mental status examination

• Order blood, urine or other tests

To get a better idea about the illness, the healthcare provider will ask many questions. Questions might include:

• What are you able to do now? How does it compare to what you were able to do before?
• How long have you felt this way?
• Do you feel better after sleeping or resting?
• What makes you feel worse? What helps you feel better?
• What happens when you try to push to do activities that are now hard for you?
• Are you able to think as clearly as you did before becoming ill?
• What symptoms keep you from doing what you need or want to do?

Patients may want to keep an activity journal. This could help them remember important details during their healthcare visit.

Doctors might refer patients to see a specialist, like a neurologist, rheumatologist, or a sleep specialist, to check for other conditions that can cause similar symptoms. These specialists might find other conditions that could be treated. Patients can have other conditions and still have ME/CFS. However, getting treatment for these conditions might help patients with ME/CFS feel better.

There is no cure or approved treatment for myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS). However, some symptoms can be treated or managed. Treating these symptoms might provide relief for some patients with ME/CFS but not others. Other strategies, like learning new ways to manage activity, can also be helpful.

Patients, their families, and healthcare providers need to work together to decide which symptom causes the most problems. This should be treated first. Patients, families, and healthcare providers should discuss the possible benefits and harms of any treatment plans, including medicines and other therapies.

Healthcare providers need to support their patients’ families as they come to understand how to live with this illness. Providers and families should remember that this process might be hard on people with ME/CFS.

Symptoms that healthcare providers might try to address are:

Post-exertional Malaise (PEM)

Post-exertional malaise (PEM) is the worsening of symptoms after even minor physical, mental or emotional exertion. For some patients, sensory overload (light and sound) can induce PEM. The symptoms typically get worse 12 to 48 hours after the activity or exposure and can last for days or even weeks.

PEM can be addressed by activity management, also called pacing. The goal of pacing is to learn to balance rest and activity to avoid PEM flare-ups, which can be caused by exertion that patients with ME/CFS cannot tolerate. To do this, patients need to find their individual limits for mental and physical activity. Then they need to plan activity and rest to stay within these limits. Some patients and doctors refer to staying within these limits as staying within the “energy envelope.” The limits may be different for each patient. Keeping activity and symptom diaries may help patients find their personal limits, especially early on in the illness.

Being mindful of personal limits could prove to be a helpful coping skill for people living with ME/CFS. This enables them the ability to find balance between activities and rest, giving them a sense of managing the illness rather than the illness controlling them. People living with ME/CFS may find that everyday activities such as buying groceries, brushing their teeth, or interacting with others may be enough to cause a relapse or “crash”. It may not be possible to entirely avoid these situations, but people living with ME/CFS need to be aware of monitoring their own activity limits. When having a good day, it is tempting to try and “push” (increasing activity beyond what would normally attempt) to make up for lost time. However, this can then lead to a “crash” (worsening of ME/CFS symptoms); the cycle can then repeat itself after people start recovering from the crash.

Rehabilitation specialists or exercise physiologists who understand ME/CFS may help patients with adjusting to life with ME/CFS. Finding ways to make activities easier may be helpful, like sitting while doing the laundry or showering, taking frequent breaks, and dividing large tasks into smaller steps. Some patients find heart rate monitors useful in keeping track of how hard their body is working, as a way to prevent PEM. Patients who have learned to listen to their bodies might be able to increase their activity level. However, ME/CFS is unpredictable. PEM symptoms may not start right after exercise, making it important for each treatment plan to be tailored for each case. Exercise is not a cure for ME/CFS.

Any activity or exercise plan for people with ME/CFS needs to be carefully designed with input from each patient. While vigorous aerobic exercise can be beneficial for many chronic illnesses, patients with ME/CFS do not tolerate such exercise routines. Standard exercise recommendations for healthy people can be harmful for patients with ME/CFS. However, it is important that patients with ME/CFS undertake activities that they can tolerate, as described above.

Sleep

Patients with ME/CFS often feel less refreshed and restored after sleep than they did before they became ill. Common sleep complaints include difficulty falling or staying asleep, extreme sleepiness, intense and vivid dreaming, restless legs, and nighttime muscle spasms.
Good sleep habits are important for all people, including those with ME/CFS. When people try these tips but are still unable to sleep, their doctor might recommend taking medicine to help with sleep. First, people should try over-the-counter sleep products. If this does not help, doctors can offer a prescription sleep medicine, starting at the smallest dose and using for the shortest possible time.

People might continue to feel unrefreshed even after the medications help them to get a full night of sleep.If so, they should consider seeing a sleep specialist. Most people with sleep disorders, like sleep apnea (symptoms include brief pausing in breathing during sleep) and narcolepsy (symptoms include excessive daytime sleepiness), respond to therapy. However, for people with ME/CFS, not all symptoms may go away.

Pain

People with ME/CFS often have deep pain in their muscles and joints. They might also have headaches (typically pressure-like) and soreness of their skin when touched.

Patients should always talk to their healthcare provider before trying any medication. Doctors may first recommend trying over-the-counter pain-relievers, like acetaminophen, aspirin, or ibuprofen. If these do not provide enough pain relief, patients may need to see a pain specialist. People with chronic pain, including those with ME/CFS, can benefit from counseling to learn new ways to deal with pain.

Other pain management methods include stretching and movement therapies, gentle massage, heat, toning exercises, and water therapy for healing. Acupuncture, when done by a licensed practitioner, might help with pain for some patients.

Depression, Stress, and Anxiety

Adjusting to a chronic, debilitating illness sometimes leads to other problems, including depression, stress, and anxiety. Many patients with ME/CFS develop depression during their illness. When present, depression or anxiety should be treated. Although treating depression or anxiety can be helpful, it is not a cure for ME/CFS.

Some people with ME/CFS might benefit from antidepressants and anti-anxiety medications. However, doctors should use caution in prescribing these medications. Some drugs used to treat depression have other effects that might worsen other ME/CFS symptoms and cause side effects. When healthcare providers are concerned about patient’s psychological condition, they may recommend seeing a mental health professional.

Some people with ME/CFS might benefit from trying techniques like deep breathing and muscle relaxation, massage, and movement therapies (such as stretching, yoga, and tai chi). These can reduce stress and anxiety, and promote a sense of well-being.

Dizziness and Lightheadedness (Orthostatic Intolerance)

Some people with ME/CFS might also have symptoms of orthostatic intolerance that are triggered when-or made worse by-standing or sitting upright. These symptoms can include:

• Frequent dizziness and lightheadedness
• Changes in vision (blurred vision, seeing white or black spots)
• Weakness
• Feeling like your heart is beating too fast or too hard, fluttering, or skipping a beat

For patients with these symptoms, their doctor will check their heart rate and blood pressure, and may recommend they see a specialist, like a cardiologist or neurologist.

For people with ME/CFS who do not have heart or blood vessel disease, doctor might suggest patients increase daily fluid and salt intake and use support stockings. If symptoms do not improve, prescription medication can be considered.

Memory and Concentration Problems

Memory aids, like organizers and calendars, can help with memory problems. For people with ME/CFS who have concentration problems, some doctors have prescribed stimulant medications, like those typically used to treat Attention-Deficit / Hyperactivity Disorder (ADHD). While stimulants might help improve concentration for some patients with ME/CFS, they might lead to the ‘push-and-crash’ cycle and worsen symptoms. “Push-and-crash” cycles are when someone with ME/CFS is having a good day and tries to push to do more than they would normally attempt (do too much, crash, rest, start to feel a little better, do too much once again).

Strategies that do not involve use of medications and might be helpful to some patients are:

• Professional counseling: Talking with a therapist to help find strategies to cope with the illness and its impact on daily life and relationships.
• Balanced diet. A balanced diet is important for everyone’s good health and would benefit a person with or without any chronic illness.
• Nutritional supplements. Doctors might run tests to see if patients lack any important nutrients and might suggest supplements to try. Doctors and patients should talk about any risks and benefits of supplements, and consider any possible interactions that may occur with prescription medications. Follow-up tests to see if nutrient levels improve can help with treatment planning.
• Complementary therapies. Therapies, like meditation, gentle massage, deep breathing, or relaxation therapy, might be helpful.

Important note: Patients should talk with their doctors about all potential therapies because many treatments that are promoted as cures for ME/CFS are unproven, often costly, and could be dangerous.

Talking about your feelings with a friend or family member can help. Sometimes it also helps to talk with people who are going through the same thing. Consider joining an ME/CFS support group.

Research shows that about half of people with ME/CFS work part-time or full-time jobs. For some people with ME/CFS, the ability to work is possible thanks to a supportive employer and certain workplace accommodations, including a flexible schedule, a quiet comfortable place to rest, and memory aids.

But, if you can't work because of ME/CFS, you may be eligible for Social Security benefits. Learn more about applying for disability through the Social Security Administration.