Are Peace Lily Plants Harmful To Cats. Peace lilies leaf, stem, flowers, and pollen are poisonous to cats. Toxicity of peace lily plants is considered mild to moderate, depending on the amount ingested.

Peace lilies are toxic to cats, and in fact, if they ingest too much, it can even be fatal. A peace lily isn’t toxic to the extent that it will kill your cat unless there is overexposure, and other pets tend to suffer even less, such as dogs. While peace lilies do not cause kidney failure as other lilies can, they do cause digestive problems and intense burning of the mouth, lips, tongue, and throat, which can make breathing difficult in rare cases if the throat swells.