What are the common symptoms of illness in cats, such as mucus diarrhea, and how should they be addressed?

Common symptoms of illness in cats include mucus diarrhea, vomiting, lethargy, decreased appetite, and changes in behavior. If you notice any of these symptoms in your cat, it is important to consult a veterinarian for a proper diagnosis and treatment plan. It is not recommended to try to address these symptoms on your own without professional guidance.