Chronic fatigue syndrome (CFS) is a disorder that causes extreme fatigue. This fatigue is not the kind of tired feeling that goes away after you rest. Instead, it lasts a long time and limits your ability to do ordinary daily activities.

The main symptom of CFS is severe fatigue that lasts for 6 months or more. You also have at least four of these other symptoms:

• Feeling unwell for more than 24 hours after physical activity
• Muscle pain
• Memory problems
• Headaches
• Pain in multiple joints
• Sleep problems
• Sore throat
• Tender lymph nodes

CFS is hard to diagnose. There are no tests for it, and other illnesses can cause similar symptoms. Your doctor has to rule out other diseases before making a diagnosis of CFS.

No one knows what causes CFS. It is most common in women in their 40s and 50s, but anyone can have it. It can last for years. There is no cure for CFS, so the goal of treatment is to improve symptoms. CFS affects people in different ways. You should work with your doctors to create a treatment program that best meets your own needs. It may include therapies to manage your symptoms, such as medicines to treat pain, sleep disorders, and other problems. It may also include coping techniques, and ways of managing your daily activities.

Centers for Disease Control and Prevention