Cats should not eat plums. Most parts of the plum—specifically the stems, leaves, and seeds (pits)—are toxic to cats because they contain cyanide compounds, which can cause serious poisoning. Even the flesh of the plum is not recommended for cats as it is high in sugar and can cause stomach upset, including vomiting and diarrhea. If a cat eats any part of a plum, especially the toxic parts, it is important to contact a veterinarian immediately as symptoms of poisoning can include dilated pupils, difficulty breathing, excessive panting, and even death if untreated.
