Feline Toxins

by Dr. Henry Phillips

Whilst there are many toxins that can cause harm to many different species of animal (such as grapes/raisins, chocolate), there are a few hazards that pose a specific risk to our feline friends. This is by no means an exhaustive list, but it is important to be aware of the following common cat toxins, to help keep your cat safe.

Lillies – whilst attractive, all parts of true and day lilies are toxic to cats (including the pollen, flowers, leaves, stem and even the water lilies are kept in!). We do not fully understand what makes lilies toxic, but once ingested lilies can cause damage to kidneys, which can result in kidney failure and death in severe cases. Clinical signs of lily poisoning include drooling/vomiting, lethargy and reduced appetite, and can occur within 1-6 hours of ingestion. Avoid  keeping lilies in the house (or garden if your cat goes outside). If your cat gets lily pollen on their fur or paws, wash it off with warm water as soon as possible, and place a buster collar to prevent them from licking and ingesting the pollen, whilst you seek advice.

Paracetamol – whilst a safe and commonly used painkiller in dogs, paracetamol in any form is extremely toxic to cats. Cats are unable to breakdown the drug, leading to formation of toxins in red blood cells and the liver. Clinical signs are usually seen within 4 hours of ingestion and include brown gums/tongue, weakness, increased heart and respiratory rate, vomiting, reduced appetite and crying. Unfortunately, paracetamol toxicity can also be fatal. Remember to never give your cat medication without being instructed to do so by your vet, and ensure your cat cannot access where you keep your medicines.

Ethylene glycol – this is the main ingredient in anti-freeze, but can also be found in car screen wash, brake and radiator fluid and some garden water features. Cats are tempted to ingest it as it often has a sweet taste. Even small amounts can be very toxic and cause permanent kidney damage. Clinical signs are seen within 0.5-12 hours and include weakness, vomiting, difficulty breathing, seizures and collapse. Consider avoiding using products containing ethylene glycol, otherwise ensure all containers are properly sealed, and all spillages are promptly cleared up.

Permethrin – permethrin is a drug commonly found in spot-on parasite treatments for dogs. As with paracetamol, cats cannot break this drug down properly, so toxins accumulate in the blood, affecting the nervous system. Clinical signs of permethrin poisoning include tremors, shaking, twitching, sensitivity to sound, wobbliness and seizures. Remember to never use a dog parasite treatment on your cat and try to avoid having permethrin-based treatments in the house altogether if possible. If your dog has a permethrin based spot-on treatment, ensure they are separated from your cat for at least 72 hours after application. Your vet will be able to advise you regarding the most appropriate parasite treatments for your pets.

What will my vet do if my cat ingests a toxin? – treatment is hugely variable depending on the toxin ingested, timeline and presenting clinical signs. Your vet may give your cat an injection to try and make them sick, perform blood tests or admit them for supportive treatment.

If you are concerned that your cat has been exposed to or ingested and toxic or hazardous substance:

  • Restrict access to the substance, including using a buster collar to prevent grooming where appropriate
  • Keep any packaging to hand so you can pass on specific information about what was ingested
  • Contact your vet or the Animal Poison Line (a 24-hour advice line run by the Veterinary Poisons Information Service for a small fee), as soon as possible
  • Never try to induce vomiting at home