The following is a short list of common feline ailments. If you suspect that your cat is suffering from any of the following or is exhibiting unusual behavior, consult a veterinarian. The most common allergy among cats is flea allergy. As cats get older, their sensitivity to flea bites increases. They can cause itching, vomiting, or diarrhea.
Vomiting Can result from hairballs, worms, food allergy, overactive thyroid, or kidney infection.
It is important to keep your cat hydrated - be sure to offer plenty of water. If your cat has persistent diarrhea, you can try changing its diet. If symptoms continue for more than 2 days, take your cat to the vet with a stool sample. The inability to pass urine can become life threatening if not treated quickly. FUS is far more common among male cats than females.