Garden and pest control
Is permethrin flea treatments toxic to cats and dogs?
Also sold as dog spot-on flea and tick treatments, some flea sprays and shampoos
Cats
Highly toxicDogs
Mildly toxicPermethrin is used in some dog flea and tick products and is highly toxic to cats. Putting a dog spot-on on a cat — or a cat grooming a freshly treated dog — can cause tremors and seizures.
By Maya HartIf your pet got into it
- If a cat was treated with a dog product, wash it off with warm water and mild washing-up liquid, keep the cat warm, and go to a vet now.
- For dogs, wash off any product that was over-applied and call your vet if they seem unwell.
Signs to watch for
- Twitching and tremors
- Seizures
- Drooling
- Dilated pupils
- High temperature
How much is dangerous
A single dog-sized spot-on can be fatal to a cat. Dogs tolerate products made for them when used as directed.
Keeping it safe
- Only use products labelled for the species and weight
- Keep cats away from treated dogs until the product has dried
- Ask your vet for flea treatments safe for multi-pet homes
The details
Cats cannot break down pyrethroids efficiently. Poisoning often happens by accident — a household with a dog and a cat uses one product for both, or buys the cheaper large-dog pack and splits it. Many modern flea treatments contain no permethrin; your vet can advise.
Questions owners ask
Is permethrin flea treatments toxic to cats?
Yes — highly toxic.
Is permethrin flea treatments toxic to dogs?
Yes — mildly toxic.
How much is dangerous?
A single dog-sized spot-on can be fatal to a cat. Dogs tolerate products made for them when used as directed.
What should I do if my pet got into it?
If a cat was treated with a dog product, wash it off with warm water and mild washing-up liquid, keep the cat warm, and go to a vet now. For dogs, wash off any product that was over-applied and call your vet if they seem unwell.
Sources
Tailwise is for general information and is reviewed by veterinary professionals, but it is not a substitute for advice from your own vet, who knows your pet. How we check facts