If your dog suddenly stops eating and only drinks water, it may be that the dog is suffering from kidney disease, uterine disease, or endocrine disease. Kidney diseases mostly refer to more serious diseases, such as kidney failure; uterine diseases are more common in pyometra; endocrine diseases are more complex and the clinical symptoms are not obvious.

It may be that your dog is a picky eater. You can try changing to some more palatable dog food, or you can add some canned food to the dog food and try to see if the dog eats it. If the dog is not eating and is not in a good mental state, it may be a loss of appetite caused by a disease. In this case, you need to take it to the hospital for a doctor to check and see what the specific situation is.