Although lilies are flowers commonly used in floral arrangements, and cats often have access to them, most cat owners and florists, are unaware of lily intoxication as a potential cause of kidney (renal) failure in cats.
Lilies are becoming especially popular as a gift in Australia, and the flowers that are sold are exceedingly toxic to cats. The key to successful treatment of these cats is early recognition of possible ingestion, and aggressive management of the ensuing renal failure. More importantly, prevention is much better than attempted cure, so it is in the interests of cat owners and cat lovers to make the danger of lily ingestion WELL KNOWN in the wider community.
Indoor cats and especially kittens, may be drawn to floral arrangements, as they are a novel feature in an otherwise very familiar environment that often lacks other forms of vegetation. In the course of investigating the flowers, the cats may play with and sometimes chew parts of the plant. This could easily go unnoticed by owners, or may occur while the cat is alone at home. Similarly, cats with access to lilies growing outdoors in domestic gardens may not be observed to contact the plant, so careful questioning regarding the presence of the plant or flowers is always warranted when a vet is investigating kidney failure in cats, especially when it develops suddenly.
The toxic substance in lilies that injures the kidneys has not been identified, but ALL parts of the lily are poisonous – flowers, stamen, stem, leaves and roots. The toxic dose is unknown, but thought to be reached by ingestion of, or mouthing, very small amounts of material.
Cats seem to be unique amongst domestic pets in their susceptibility to this intoxication, possibly due to differences in their metabolism. For the same sort of reason, cats also can be easily poisoned by human medications such as paracetamol, ibuprofen and aspirin, and these too are lethal for cats in doses that would be safe for humans. Interestingly, dogs that consume large amounts of the plant develop only mild gastrointestinal signs, while rats and rabbits show no signs of toxicity at all.