Many times there are gastrointestinal problems stated as being constipation to diarrhea for the same person. You will see this in the group of CFS, CFIDS, FM, ME. It is most probably an autoimmune issue that elevates to a cessation of the bowels functioning: the intestines, large/small.
Diarrhea is what exposure to the chemical that causes these would often look like. Gulf war syndrome vets complain about this and the other issues of CFIDS.
... or at least the intestines seemed to have ceased functioning I think the diarrhea is a reaction to exposure to Ethylene Glycol Monobutyl Ether .... and
That's more than just constipation ... can elevate to an autoimmune issue in which the intestines lock up and cease to function. May be Locked Bowel Syndrome