Paracetamol should never be given and should be kept out of reach of cats to prevent accidental ingestion. Acetaminophen can cause a decrease in the red blood cells' ability to carry oxygen. Liver damage may also occur, and red blood cell changes can occur within 4-12 hours. Cats may become depressed or weak, with rapid breathing, a high heart rate, painting, abdominal pain, vomiting, or drooling.