A. Vomiting up yellow bile, seeming like he is constipated (which may seem like he is but I am more inclined to think you are seeing your pet strain which is commonly mistaken for constipation but ends up being because of an inflamed colon and not hard feces) and not eating food area all signs that are suspicious of pancreatitis. Pancreatitis can happen in pets that are fed people food and also in pets that are not but are predisposed to the disease. It is an inflamed pancreas and can be painful to pets. You should go to a vet for this because if this is what I presume it is, then your pet needs a lot of supportive care (i.e. Fluid therapy, antibiotics, pain meds, nausea meds, antacids) to hopefully help him recovery from this. This is a disease where the quicker you act and get your pet help, the better their chances are at recovery.
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