Symptoms of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome

Key points

  • Myalgic Encephalomyelitis/Chronic Fatigue Syndrome symptoms are common in many other illnesses.
  • There is no test to confirm ME/CFS. This makes it hard to diagnose.
  • Symptoms are unpredictable and may change or come and go over time.
  • However, a combination of core symptoms are used to diagnose ME/CFS.
female doctor holding a patient clipboard to discuss and analyze the patient's condition before treating

Primary symptoms

ME/CFS has five core symptoms. You must have three main ME/CFS symptoms and at least one of the other two symptoms to be diagnosed with ME/CFS.

Less ability to do activities and fatigue (required)

People with ME/CFS have a much lower ability to do activities they could do before they got sick. This limitation comes with fatigue and lasts six months or longer.

The fatigue:

  • Can be severe
  • Isn't caused by an unusually difficult activity
  • Isn't relieved by sleep or rest

Worse symptoms after activity (required)

People with ME/CFS experience a worsening of their symptoms after any type of activity - physical or mental. These activities wouldn't have been a problem before they became ill. This is called Post-Exertional Malaise (PEM).

PEM can lead to a cycle of "pushing" to do more, followed by "crashing." During a crash, people with ME/CFS may have a variety of symptoms. These can include difficulty thinking, problems sleeping, sore throat, headaches, feeling dizzy, or severe tiredness.

It may take days, weeks, or longer to recover from a crash. Some people may be confined to bed or the house. As examples:

  • Attending a school event may leave someone house-bound for days.
  • Grocery shopping may require a nap in the car before driving home.
  • Doing errands may require getting a ride home.
  • Showering may leave someone bed-bound for days.
  • Working may mean spending nights and weekends recovering.

Sleep Problems (Required)

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

Additional symptoms (At least 1 required)

In addition to the three required symptoms above, one of the following two symptoms is needed to be diagnosed with ME/CFS.

Memory and thinking problems

Most people with ME/CFS have trouble thinking quickly, remembering things, and paying attention to details. People with ME/CFS often say they have “brain fog” to describe this problem. This is because they feel “stuck in a fog” and not able to think clearly.

Problems being upright

People with ME/CFS often report their symptoms get worse when they are standing or sitting upright. This is called orthostatic 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
  • Frequent sore throat
  • Digestive issues, like irritable bowel syndrome
  • Chills and night sweats
  • Allergies or sensitivities to foods, odors, chemicals, light and noise
  • Muscle weakness
  • Shortness of breath
  • Irregular heartbeat
  • Disclaimer: This website is for informational purposes only. The information provided on this website is not intended to be a substitute for professional medical advice, diagnosis, or treatment.