Multiple Chemical Sensitivity: Towards the End of Controversy

There are nine well accepted paradigms of human disease. The tenth may explain the features of multiple chemical sensitivity (MCS) and a group of related illnesses including chronic fatigue syndrome (CFS), fibromyalgia (FM) and posttraumatic stress disorder (PTSD); Gulf War syndrome appears to be a combination of all four. The elevated nitric oxide/peroxynitrite vicious cycle paradigm explains most of the most puzzling features of this group of previously unexplained illnesses (1-16) that afflict tens of millions of people in the U.S. and elsewhere. These illnesses have multiple overlaps with each other (2-5,13,16). They share many common symptoms and signs. They are repeatedly reported to be comorbid conditions. Cases of each of them typically show a common pattern of case initiation, with cases being preceded by and presumably induced by a short term stressor, only to be followed by a chronic illness that usually persists for life. These similarities have led many different researchers to propose that two, three or all four of them may share a common etiologic mechanism (3,5,16), but they were unable to suggest what that mechanism might be.