Lilies are extremely toxic to cats. Lily toxicity in cats is an emergency. If you suspect lily toxicity, seek immediate veterinary attention.
Lilies (Lilium spp and Hemerocallis spp. – common names include Easter, Asiatic, Tiger, Stargazer, Calla, Leopard, Panther, Yellow, Trumpet, White and Day lilies) contain substances that are extremely toxic to cats [1].
All parts of the lily plant are toxic, including petals, stems, leaves, and pollen [1,2]. Note that, even the water in a vase of cut lilies is thought to be toxic, and the pollen can fall onto the cat’s hair and be ingested via grooming. Ingesting even just small amounts can cause rapidly fatal kidney failure (generally within 12 to 72 hours of ingestion) [1,2].
Symptoms of lily toxicity in cats include vomiting (may contain bits of lily), excessive salivation, and signs associated with kidney failure including disinterest in food, depression, lethargy, dehyrdation, excessive or no urination, and death [1,2].
The keys to a chance of successful treatment are early recognition of lily toxicity, and prompt veterinary management of kidney failure.
Make sure your cat never has access to lilies of any kind, including cut flowers, pot plants, or in garden beds.
References
[1] Fitzgerald KT (2010) Lily Toxicity in the Cat. Top Companion Anim Med 25:213–217
[2] Bertero A, Fossati P, Caloni F (2020) Indoor Companion Animal Poisoning by Plants in Europe. Front Vet Sci.