Go back to the vet. They usually treat obvious first, then more aggressive as needed. How long has it been since you gave dog the pill? Does your vet know he is not getting better? Is Dog eating, drinking, panting a lot,? Defecating or urinating at all? Some things do not show up on x-rays. Socks, plastic bags,toys. There could be a twist in the intestine, which could cause intestines and dog to die. A vet many times can not instantaneously diagnosis a problem or a give a diagnosis over the phone. Could be anything from an upset stomach to gastric torsion. Your vet probably treated the most obvious first. Don't want to operate if not warrented. It is our job as guardian's of our pets, to keep vet informed of pet's condition. More aggressive treatment if needed. Sounds like your Dog needs it. Maybe she's old. Maybe gas. Good luck A sick dog does not mean a bad owner.