Flea, tick & worm products · cat safety
Can I use my dog's flea spot-on on my cat?
Deadly
No — never put a dog's flea or tick spot-on on a cat, not even 'just a few drops'. Many dog products contain permethrin, which cats can't break down: it causes twitching, tremors, seizures and sometimes death. Cats can also pick it up by cuddling or grooming a freshly treated dog. Go to a vet now.
Why deadly: Cats can't clear permethrin: a dog spot-on on a cat — or cuddling a freshly treated dog — causes tremors and seizures, and some cats die.
- Name
- Dog flea and tick spot-ons (permethrin)also Permethrin, Imidacloprid + permethrin dog spot-ons, Pyrethroid dog sprays, shampoos and soaps, Permite and other permethrin scabies creams, Splitting a dog pipette for a cat
- Hindi
- कुत्ते की पिस्सू दवा
What counts
Spot-on pipettes, sprays, shampoos, soaps and collars for dogs that contain permethrin or another pyrethroid — and human scabies or lice creams with permethrin.
What's in it
Permethrin, a pyrethroid insecticide. Cats lack the liver pathway (glucuronidation) to clear it quickly, so it keeps their nerves firing — cats are more sensitive to pyrethroids than other pets (Merck).
Brands it hides in
- Any pack that says 'for dogs only' or shows a dog
- Ingredient lists with permethrin, cypermethrin, deltamethrin or flumethrin
- Human scabies and lice creams such as Permite (permethrin)
- A cat-labelled product from your vet is the only safe choice
Symptoms to watch for
- Twitching ears and skin, paw flicking
- Muscle tremors
- Drooling
- Wobbly walking, wide pupils
- Seizures
- Breathing difficulty; temporary blindness in some cats
Usually within a few hours, but can take up to 36 hours (PDSA). Tremors often last more than a day, and most cats need 2–3 days to recover (UK VPIS series).
What to do — now
Go to a vet now — don't wait for tremors. Vets wash the product off and control the tremors; there is no antidote.
- Take the pipette or box.
- Ask your vet on the phone whether to wash the spot with mild dish soap and lukewarm water before you come — washing can increase absorption of some chemicals, so do it only on their advice.
- Don't make your cat vomit at home unless a vet tells you to.
- Keep cats away from a freshly treated dog until the product is completely dry.
Where Indian cats meet it
Multi-pet homes: the dog's spot-on or shampoo used on the cat to save money, a cat sleeping against a freshly treated dog — or a family scabies cream with permethrin tried on an itchy cat.
Myth or fact
Myth“A few drops from the dog's pipette is a safe cat dose”
FactOwners often assume a smaller amount of a dog product is safe — it isn't: 'Never use a dog product on a cat' (International Cat Care). Of 286 UK cases, almost every cat fell ill and about one in ten died (Sutton et al. 2007).
Cat-safe swap: Ask your vet for a flea and tick treatment labelled for cats.
Sources
- International Cat Care: Permethrin poisoning
- Sutton et al. 2007, JFMS: 286 feline permethrin spot-on poisonings, UK VPIS (PubMed)
- PDSA: Permethrin toxicity in cats
Facts last checked
General information for cat parents, not a diagnosis or a treatment plan. The facts come from ASPCA, Pet Poison Helpline, International Cat Care, the Merck Veterinary Manual and the other sources listed on every page — and we say so when the evidence comes from dogs or people. If your cat may have eaten something harmful, call your vet.