Iresine Syndrome
From Star Trek : Freedom's Wiki
A very rare neurological disorder in humanoids characterized by a peculiar electropathic signature in the thalamus, and a severely decreased histamine count. Victims of the disorder, first identified in the 23rd century, would fall suddenly into a coma for approximately 72 hours. Diagnosis could be confused by the presense of any of 22 different substances that left electropathic residue resembling that of this disorder.