Good to know for cat owners: lilies are a real threat to their pets’ lives

Both of the true lily plants, Lilium sp. and Hemerocallis sp., can result in acute kidney injury or toxicosis in cats and can be fatal if left untreated. True lilies include Easter lilies, tiger lilies, Asian lilies, stargazer lilies, daylilies and lily hybrids.

Even a small interaction with one of these lily plants — a lick of pollen, a bite of a leaf or a drink of water from the vase — can have catastrophic consequences for cats.

Signe Roberts, a fourth-year veterinary student at the Western College of Veterinary Medicine (WCVM), is very familiar with the clinical signs of lily poisoning.

“I've seen a few cases at the clinic that I'm working at — we actually have a case in today,” says Roberts, who is spending her summer working at Glenview Animal Hospital, a veterinary clinic in British Columbia.

While the patient’s owners didn't witness their senior pet ingesting parts of a lily flower, they noticed bite marks on the lily petals. They quickly brought their cat to the clinic — alongside a photo of the chewed flower for the veterinary team to identify — and the cat was immediately put on a high dose of intravenous fluids and closely monitored.

“This cat also has different health problems that put it at a high risk of going into renal failure, so we had to act quickly,” says Roberts. “It's a good outcome, I think, for this cat. But we see these cases all too regularly.”

As a third-year veterinary student, Roberts took part in a research study focusing on lily toxicity in cats with Dr. Vanessa Cowan, a veterinary toxicologist at the WCVM. By analyzing data from lily poisoning cases at the college’s Veterinary Medical Centre (VMC) in the past five years, the study aims to detect patterns in presentation, progression and outcomes of feline lily toxicity cases.

“We collected all of that data and worked through how they presented, what the signalment was, the time from the exposure to the actual presentation of the case, and basically how that case ran through the hospital,” says Roberts.

Roberts first became involved in the study after Cowan, an assistant professor in the WCVM’s Department of Veterinary Biomedical Sciences, came to her class and offered the study as a research opportunity for a third-year elective course.

“I always wanted to get involved in research, but I never really had the opportunity with my undergraduate degree,” says Roberts. “I thought this was a really good opportunity.”

While data was collected from 2018 to 2023, Roberts’ research project focused on cases reported in 2018 and 2019. Based on her study’s findings, lily poisoning cases often follow a very similar pattern.

“When it starts off, they have gastrointestinal problems — vomiting, not wanting to eat … maybe being a little bit lethargic,” says Roberts. “And then after they get past [the first] six to 12 hours of gastrointestinal upset, they may potentially start experiencing signs more consistent with renal failure.”

Lily poisonings are by far the most common toxicity case in cats seen at the VMC, with over 100 cases in the last five years. Clinicians had to humanely euthanize three of those feline patients due to renal failure.

Roberts says one of the study’s key findings was the critical role that time plays in the successful treatment of cats affected by lily poisoning.

“In animals that presented within six hours of having eaten the leaf or sniffed the pollen or drank the water that the lilies were in, they tended to have a much better prognosis than those that presented 48 hours afterwards,” says Roberts.

The study also found that an increase in lily toxicity cases correlates to certain holidays or seasons.

“Lilies are such a common ornamental flower in almost every flower arrangement that you find,” says Roberts. “Mother's Day, Valentine's Day — we see a lot of poisoning cases. All throughout the summer, we also saw a lot of cases from the wild prairie lily.”

Roberts says pet owner education about the dangers of lilies is lacking.

“I think [lily poisonings are] something that is so easily preventable. But a lot of people just don't know about lily toxicity in cats,” says Roberts.

In a 2011 study, researchers found that only 69 per cent of cat owners could identify a lily and only 27 per cent knew that lilies were toxic before their cat’s exposure.

Roberts plans to expand her lily toxicity study’s scope to include additional years of cases at the VMC. Overall, she remains hopeful that educating cat owners and the public will result in fewer toxicity cases.

“Education for me is the primary thing,” says Roberts. “I hope that with this research and with other vets becoming more cognizant of it, we can do better at promoting prevention of common toxicities.”