Dehydration . . . the vagus nerve . . . :
 

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Patients might be wise to be able to quickly detect dehydration . . . the possibility of gastro-intestistinal track paralysis is little discussed in the literature . . . if the vagus were to become involved in the disease processes of ALS. My best guess regarding bulbar onset ALS's short life expectancy is the involvement of the vagus nerve. Patients are often fine until the last three months or so of the disease, possibly because gastro-intestinal track paralysis cause food and liquid to decrease the rate of processing in the GI track.