Chronic fatigue syndrome/Myalgic Encephalomyelitis (CFS/ME) is a complex and debilitating multi-system, chronic disease that causes extreme, persistent fatigue and flu-like symptoms that lasts greater than six months. The key symptom of ME/CFS is post-exertional malaise (PEM), the worsening of symptoms following even minor physical or mental exertion, with symptoms typically worsening 12 to 48 hours after activity and lasting for days or even weeks. Other symptoms include unrefreshing sleep, brain fog, orthostatic intolerance, photophobia, GI abnormalities and headache. Many of these symptoms overlap with migraine.
In one study, migraine and tension headache were found to be prevalent in 84% and 81% of the CFS subjects, respectively, compared to 5% and 45% of those in the control group.1