The symptoms of chronic fatigue syndrome (CFS) vary widely between individuals but usually symptom onset is sudden, with an affected person becoming persistently or frequently tired for no apparent reason.

Diagnostic criteria are based on a pattern of symptoms which are observed over time as no one symptom or laboratory test can confirm a diagnosis of CFS. The Centers for Disease Control and Prevention recommends that a diagnosis of CFS is considered when the fatigue is:

• Unexplained, new and persistent or recurring
• Is not relieved by rest or sleep
• Interfering with activities of daily living

In addition, one of the following features should be present:

• Sleeping difficulties such as insomnia, over sleep, disturbed sleep
• Muscle and joint pain across multiple sites that does not seem to be caused by inflammation
• Headaches
• Painful but not enlarged lymph nodes
• Sore throat
• Cognitive problems such as clouded thinking, lack of concentration, short-term memory loss and problems with thought processing and word formation
• General malaise or flu-like symptoms
• Dizziness and/or nausea
• Palpitations but not cardiac pathology

Other associated factors and symptoms include:

• Work or school absenteeism
• Reduced mobility and inability to care for self
• Abdominal bloating and pain with constipation, diarrhea and nausea
• Sensitivity or intolerance to light and loud noise
• Allergic tendencies to certain foods, medications and chemicals
• Mental health problems such as depression or anxiety

Further Reading

• All Chronic Fatigue Syndrome Content
• What is Chronic Fatigue Syndrome?
• Chronic Fatigue Syndrome Pathophysiology
• Chronic Fatigue Syndrome Classification
• Chronic Fatigue Syndrome Treatment

Written by

Dr. Ananya Mandal

Dr. Ananya Mandal is a doctor by profession, lecturer by vocation and a medical writer by passion. She specialized in Clinical Pharmacology after her bachelor's (MBBS). For her, health communication is not just writing complicated reviews for professionals but making medical knowledge understandable and available to the general public as well.