The Chronic Fatigue Syndrome Symptoms to Know if You're Always Exhausted

As the name suggests, it’s an exhausting illness: People with chronic fatigue suffer an unexplained and extreme feeling of tiredness that can last for many months, and often years.

“Their ability to do functional activities—activities of daily living—are impacted dramatically,” says Betsy Keller, PhD, a researcher and professor in the Department of Exercise and Sport Sciences at Ithaca College.

Until recently, there was a widespread misconception—even among doctors—that the disorder was psychological, or worse, imagined. But that notion was put to rest by a government panel of experts in 2015 that defined chronic fatigue as a “serious, debilitating condition” with clear physical symptoms.

The Institute of Medicine (IOM) committee estimated that as many as 2.5 million Americans have the illness—and at least 84% of them haven’t yet been diagnosed. “Patients often struggle with their illness for years before receiving a diagnosis,” the panel wrote in a report that recommended new diagnostic criteria and called for more research on the mysterious disease.

While there is no cure for chronic fatigue, its symptoms can be treated with various drugs and therapies—from sleep aids and pain relievers to gentle exercise and counseling. “We see people that are managing their lives reasonably well,” says Chris Snell, PhD, chair of the scientific advisory committee to the Workwell Foundation, which is dedicated to chronic fatigue research. However, he says, early diagnosis and treatment may be key to recovery. “I suspect the longer you’ve had the illness, the more effect it’s had on your system.”

Read on to learn more about the syndrome—and signs that it’s time to get long-lasting fatigue checked out by a doctor.

“The likelihood is that it’s a genetic predisposition [plus] a particular trigger,” says Snell, who formerly served as chair of the Chronic Fatigue Advisory Committee to the United States Secretary for Health.

The fact is, the exact cause remains a mystery—and there could very well be multiple causes, according to the U.S. Centers for Disease Control and Prevention (CDC).

Research suggests that infection with the Epstein-Barr virus, and possibly other infections, may trigger some cases of the disease. Other possible causes that scientists have investigated include immune system problems and hormonal imbalances. But there haven’t been any definitive findings to date.

Chronic fatigue affects people of both sexes and all ethnic and economic backgrounds. Women, however, are four times more likely to be diagnosed with the syndrome than men. Caucasians are also more likely to be diagnosed, the IOM report found, but some research suggests minorities are actually at greater risk.

The illness can strike at any age, even during childhood, and is most common among people in their 40s and 50s. As the CDC points out, it afflicts more people in the U.S. than multiple sclerosis and many types of cancer.

There’s no lab test, or biomarker for chronic fatigue, and its symptoms overlap with many other illnesses, which makes diagnosing the disorder a challenge. “[Chronic fatigue] looks like a lot of other things,” says Snell.

The fact that it’s a complex disorder with diverse symptoms throughout the body complicates matters further. “Most physicians are not trained in medical school to look at more than eight or 10 symptoms without thinking psychiatric disorder,” says Keller. “They don’t know what to do with it, and if they can’t put a label on it, it creates problems.”

According to the authors of the IOM report, less than half of medical textbooks include information on chronic fatigue, and fewer than a third of medical schools cover it in their curricula.

To diagnose the disease, a doctor must rule out other fatigue-causing disorders, and identify the telltale signs of chronic fatigue described in the slides ahead.

This is not weariness after a taxing week. This is profound fatigue that leads to a sharp reduction in your ability to function on a day-to-day basis—and lasts for six months or more.

The tiredness isn’t brought on by excessive activity (say, moving to a new city, or training for an IronMan), but by activities you could once do easily. “Even sitting for a long period of time in an uncomfortable position could generate symptoms,” says Snell.

The tiredness is unrelenting, and does not go away with rest. The IOM report found that at least a quarter of people with chronic fatigue become home- or bed-bound at some point.

The technical term is post-exertional malaise. It means that when you put more stress (physical, mental, or emotional) on your body than it can handle, your symptoms flare. “[A patient’s] lymph nodes might swell up,” says Keller, “or they might have joint pain, or pain in other areas.”

The authors of the IOM report quote one patient who described it like this: “When I do any activity that goes beyond what I can do—I literally collapse—my body is in major pain. It hurts to lay in bed, it hurts to think, I can’t hardly talk—I can’t find the words. I feel my insides are at war.”

It may take a full day to recover, or longer.

People with chronic fatigue can log 12 hours in bed, “but when they get up, they feel like they haven’t slept at all,” says Keller. The IOM committee dubbed this phenomenon “unrefreshing sleep.”

Most people with chronic fatigue develop a sleep problem of some kind that they didn’t have before, according to the CDC. The common complaints—including insomnia and frequent awakening—can leave people depleted in the a.m., rather than restored.

That’s why for people with chronic fatigue, conserving the energy they do have is so important, says Keller. “The patients who are functioning best tend to be those who learn to manage their available energy,” she explains. “They’re probably managing their symptoms better because they’re living at a much lower intensity of effort.”

Some people with chronic fatigue experience some “cognitive impairment,” according to the IOM panel. “Mostly what happens is they have a delay in their ability to process information,” explains Keller. “They can still process information, but they can’t do it quickly.” They may also have blips in their short-term memory, she adds.

These problems with mental processes—which may also include difficulty paying attention, problem solving, and planning—can make it difficult to hold down a job, or interact in social situations. And the issues get worse when you’re stressed, or you’ve over-exerted yourself. Unsurprisingly, they can lead to feelings of isolation and hopelessness.

For many chronic fatigue patients, the simple act of standing upright—in the shower, for example, or while doing dishes—can lead to feelings of dizziness and lightheadedness, and possibly fainting. When the person lies down or elevates her feet, the symptoms get better, but don’t necessarily disappear.

This phenomenon is what doctors call “orthostatic intolerance.” It’s linked to chronic fatigue’s effect on the autonomic nervous system, says Keller, which is “the part of the nervous system that controls everything that’s automatic in our bodies”—including circulation. Chronic fatigue is known to lead to problems with blood pressure and blood flow, she says.

Pain is a common symptom of chronic fatigue—but it can come in many forms, from headaches to joint and muscle pain. It also differs in intensity from one person to the next, according to the IOM panel experts. In their report, they quoted a patient with a particularly severe case: “My personal experience with [chronic fatigue] feels like permanently having the flu, a hangover, and jet lag while being continually electrocuted (which means that pain plays at least as much of a role in my condition as fatigue).”

There are several additional complaints that chronic fatigue patients report, though less frequently. “I would say more often than not people have gastrointestinal issues,” says Snell. Others on the list include a sore throat, tender lymph nodes in the neck and armpits, problems in the genitourinary system (including gynecological issues), and sensitivity to certain drugs, foods, chemicals, or other stimuli.

If you recognize the signs of chronic fatigue in yourself—especially the severe exhaustion, post-exertional malaise, and unrefreshing sleep—talk to your MD. If you do have the disorder, the sooner you’re diagnosed, the sooner you can get the treatment you need to feel better.