Cat Not Eating Lethargic. He also is not producing stool. If a cat has not eaten for 24 hours, take him to the veterinarian.
Taking care of your cat is one of the most important things you should prioritize. A small percentage of cats who develop hyperthyroidism go the exact opposite route with symptoms, and show a decreased appetite, lethargy and depression instead of behaving like a hyperactive hummingbird. If a cat is sick, it will be weak and lethargic.
Your cat's lack of eating can also be a symptom of a disease or problem that's causing pain or discomfort.
Why it's a problem if your cat stops eating. First and foremost, the cat is lethargic and not eating. Our cat will not eat or drink and she is lethargic. Regardless of the reason, it's a major concern if your cat stops eating.