No, amoxicillin does not make cats hungry. In fact, it is often used to treat infections in cats that can cause anorexia (loss of appetite). Amoxicillin is a safe and effective antibiotic that is typically well-tolerated by cats. The most common side effects are vomiting and diarrhea, which usually resolve within a few days. If your cat is taking amoxicillin and begins to show signs of anorexia, please contact your veterinarian for further instructions.