Medically reviewed by Dr Sam Kovac BVSc (Merit) – Southern Cross Veterinary Clinic
At a glance
Lilies are popular in floral arrangements, but while we may admire their beauty, they are deadly to cats. Cat owners need to be aware that having these flowers in your home can prove fatal. Lilies are a nephrotoxin, which are toxins affecting the kidneys, causing acute kidney failure due to the death of the renal epithelial cells.
Although any cat is at risk, indoor cats and kittens are particularly vulnerable. The exact toxin isn’t known, but what is understood is that it is water-soluble and ingestion leads to the death of the renal tubular epithelial cells through a mechanism that isn’t yet understood.
If you suspect your cat has eaten any, immediate veterinary attention is vital.
Which parts are toxic?
All parts of the plant are poisonous including the leaf, stamen, pollen, flowers and as little as 2 leaves or part of a single flower have resulted in deaths.
Lilies of the genera Lilium and Hemerocallis are toxic to cats. Below are images of some common toxic lilies to make identification easier.
Common species include:
There are two stages of lily poisoning in the cat; the first stage occurs due to gastrointestinal upset followed by acute kidney failure.
Early clinical signs
- Vomiting which may contain parts of the ingested plant in the vomit
- Loss of appetite
- Increased urination
Vomiting usually subsides a few hours after exposure, although anorexia and depression typically remain. Kidney failure occurs 12-72 hours post-ingestion.
Clinical signs associated with kidney failure
- Abdominal pain
- Bad breath
- Once the kidneys have become damaged, urination will be absent
- Increased or decreased thirst
If urination decreases, hyperkalemia (high blood potassium) can develop as it is the kidney’s role to remove excess potassium from the blood via the urine.
Clinical signs of hyperkalemia
- Cardiac arrhythmias
- Muscle weakness
There are no specific tests available to diagnose lily poisoning. The veterinarian will perform a thorough physical examination which may reveal painful and enlarged kidneys. A thorough medical history will include the onset of symptoms and exposure to toxins. A timeline is important to determine how long ago ingestion occurred.
- Chemistry panel: Groups of tests of a sample of the cat’s blood may reveal elevated blood urea nitrogen (BUN) and creatinine, both of which are indicative of kidney failure.
- SDMA test: This new rapid blood test can evaluate for early kidney damage, for biochemistry tests to pick up kidney failure, 70% of kidney function must be lost, by which time irreversible kidney damage has occurred. The SDMA test can detect as little as a 25% decline in kidney function.
- Urinalysis: A sample of urine can provide additional information on the extent of kidney damage and urine-concentrating ability.
- Kidney ultrasound: This enables the veterinarian to evaluate the size of the kidneys and evaluate for concurrent problems such as kidney stones, infection (pyelonephritis), tumours and blood clots which may complicate recovery. Where available CT scanning is much faster than ultrasound to diagnose concurrent problems.
- Kidney biopsy: A small sample is taken from the kidney to evaluate the cells.
- Blood pressure: It is important to check the cat’s blood pressure as hypertension can occur in cats who have ingested lilies.
Prompt medical treatment is vital; the sooner your cat sees a vet, the better his chances of recovery. A high mortality rate is reported if treatment is not initiated before the onset of anuric renal failure, which occurs 18–24 hours after exposure. Even with medical treatment, there is no guarantee the cat will survive, but the chances greatly decrease if treatment doesn’t commence before renal failure.
There is no antidote for lily poisoning and treatment is aimed at removing any remaining plant material, preventing further absorption and providing supportive care.
- Gastrointestinal tract decontamination: Inducing vomiting, followed by administration of activated charcoal to bind to the toxins in the gastrointestinal tract and must be performed within 1-2 hours of ingestion.
- Intravenous fluid therapy: To maintain urine production is the mainstay of treatment, which will continue for 48-72 hours. The purpose of fluid diuresis to maintain urine production to speed up the removal of toxins in the blood (uremic poisoning) as well as treat dehydration.
Once the kidneys have stopped working, dialysis is necessary to remove toxins from the blood, there are two types of dialysis.
- Peritoneal dialysis: A catheter (thin plastic tube) is placed into the peritoneal cavity and uses the peritoneal membrane as a filter to remove wastes from the blood when the kidneys are unable to perform this function. Dialysis solution enters the peritoneal cavity via the catheter, excess fluids and waste products from the blood pass through the peritoneal membrane and into the dialysis solution. After some time, the solution is drained out of the peritoneal cavity.
- Hemodialysis: A dialysis machine and a special filter (artificial kidney) is used to remove wastes from the blood which would ordinarily be performed by the kidneys. Blood is passed out of the cat’s body and into the dialysis machine where it is cleaned and returned to the body.
- Anti-nausea medication for cats who are vomiting.
- Blood pressure monitoring.
- Monitor urine output.
- Feed a low-protein, low mineral diet to place as little load on the kidneys as possible during recovery.
Prognosis is good for cats who receive treatment before anuria (absent urination) has occurred, but it is poor once the kidneys stop producing urine.
Cat owners need to be aware of the dangers of keeping lilies in their home and garden and avoid having these extremely dangerous plants around cats.
When ordering flowers for friends or relatives, make sure they do not contain lilies of the genera Lilium and Hemerocallis if a cat is living in the household.
Frequently asked questions
Can peace lily kill my cat?
Peace lily (Spathiphyllum spp.) contains insoluble calcium oxalate crystals which penetrate the oral mucosa when any part of the plant is chewed. Clinical signs include pawing at the mouth, drooling and redness of the gums which can look dramatic but exposure is not deadly.
Can cats be in the same room as lilies?
It is not a good idea to have lilies in the same room as cats. Even if they don’t chew on the flowers, stems or leaves, they may drink the water or their coat may be contaminated with pollen as they brush past which they may then ingest during grooming.
Are dried lilies toxic to cats?
How much lily will kill a cat?
There is no data on how much exposure will kill a cat, what we do know is lilies are fatal, and therefore any amount of exposure, no matter how small requires urgent veterinary attention.