
These areas may also develop a chocolate brown color from the methemoglobin (which cannot carry oxygen to tissues). Their mucous membranes, such as the gums or tissue around the globe of the eye, may develop a bluish color called cyanosis. Signs of toxicity from acetaminophen may develop within 1–4 hours of ingestion. Acetaminophen can cause a decrease in the red blood cell’s ability to carry oxygen (methemoglobinemia). Liver damage may also occur. Red blood cell changes can occur within 4-12 hours. Cats may become depressed or weak, with rapid breathing, a high heart rate, panting, abdominal pain, vomiting or drooling.

What are the signs of acetaminophen toxicity in cats? Cats develop toxicity at much lower doses than in dogs. Since cats are not able to efficiently metabolize acetaminophen, they are more vulnerable to toxicity. Unfortunately, this is relatively common toxicity, due to owners trying to treat their cat’s pain at home. Less commonly, cats may get into the owner’s medication. Acetaminophen, a common human drug used to control pain and fever, is toxic in cats.
