Core Symptoms
ME/CFS is characterized by several hallmark symptoms that must be present for diagnosis across most diagnostic frameworks. This chapter provides detailed descriptions of each core symptom.
For patients: read the post-exertional-malaise section (Post-Exertional Malaise (PEM)) first to understand the crash that pacing must prevent, then the fatigue (Fatigue) and unrefreshing-sleep (Unrefreshing Sleep) sections. The cognitive (Cognitive Impairment) and pain (Pain) sections explain common experience.
For caregivers: read the defining core-symptom sections (Post-Exertional Malaise (PEM), Fatigue, Unrefreshing Sleep, Cognitive Impairment) to recognize the features and why exertion causes worsening, and the sensory-sensitivities section (Sensory Sensitivities) for symptom triggers.
For clinicians: read the PEM section (Post-Exertional Malaise (PEM)) as the diagnostic anchor, and the fatigue, cognitive, autonomic, pain, and sensory sections (Fatigue, Cognitive Impairment, Autonomic Dysfunction, Pain, Sensory Sensitivities) for assessment of the defining features.
For researchers: read the PEM (Post-Exertional Malaise (PEM)), fatigue (Fatigue), and cognitive (Cognitive Impairment) sections for precise symptom definitions used in case selection and phenotyping.