Although many varieties of lilies are dangerous only to cats, the beautiful peace lily is poisonous to both cats and dogs. Even a small piece of the plant can make your precious pet violently ill. In some cases, it can even be deadly.
Peace lilies are moderately toxic. Even a small amount can cause symptoms in a cat or dog, but it does not cause kidney damage like many other lilies since it is not a true lily. A dog's or cat's reaction to a peace lily is caused by small crystal-like formations within the plant's cells. These actually shoot out of the plant when it is bruised or broken, causing irritation of the mouth and gastrointestinal tract.
Chewing and Ingestion
Chewing on the leaves, stem or flowers of the plant is the most common method of ingestion. Even if the dog or cat does not swallow pieces of the plant, he is likely to have a reaction simply from making contact through chewing. Some cats are especially sensitive and could have a reaction simply from licking pollen from the peace lily off of their paws or fur. Peace lilies should be kept far out of reach of both dogs and cats.
Vomiting, drooling and diarrhea are the most common symptoms of peace lily ingestion. More dangerous symptoms include swelling of the throat, nose, lips and tongue as well as difficulty breathing. Dogs and cats experiencing a reaction to chewing on or eating a peace lily will also often paw at their faces and mouths because of the irritation.
Dogs and cats love to chew things they're not supposed to, and despite your precautions they may get involved with this somewhat toxic plant. If this happens, don't panic—your pet may be uncomfortable, but it's unlikely she'll suffer long-term ill effects. First remove any pieces of the lily from her mouth and the surrounding fur, and flush her paws with cool water to remove any remaining irritants. If your pet is having difficulty swallowing or breathing, or vomiting and diarrhea are severe, contact a veterinarian immediately. Antihistamines or steroids will often be prescribed to counteract the body's reaction to the peace lily. Never try to make your pet vomit without first contacting a veterinarian or the National Animal Poison Control Center; it can make some situations worse.