My cat had the same syntoms, the vet detected crystal obstruction, the good thing was that we only had to change his food, and now he is perfect, just act fast. My vet told me that Wiskas was the worst cat food brand of all, and that this was what caused the obstruction.
This is my story... I have always been a cat lover since I was a child. When I got married a friend on mine found Lolo, a lovely kitten lost in the middle of the mountain, at least two miles away from civilization. He was biking with his dog and Lolo followed him a long way and stayed outside...
