Permethrin poisoning in cats – signs and what to do

Updated 2026-09-30 · 2 sources

Based on: PDSA, International Cat Care (iCatCare)

See a vet now

This is an emergency – contact your vet or the nearest emergency vet right now. Permethrin poisoning is poisoning in cats caused by permethrin.

What to do now

What you can do now

Contact your vet or the nearest emergency vet now.
Note when it started, how often it happens and what else you see.
Take a photo or short video to show the vet.
Keep fresh water available.
Let your cat rest somewhere calm.

Don't

Do not give any human medicine.
Do not wait if it gets worse.

What it is

Permethrin is highly toxic to cats and is used in some flea products for dogs and, in lower doses, some flea powders and collars for cats.^[2] Left untreated, permethrin poisoning is usually fatal.^[1]

Signs

Tremors or shaking
Twitching
Oversensitivity to touch and sound
Wobbling or loss of coordination when walking
Seizures or fits
Drooling
Wide pupils
Struggling to breathe

Causes and risk factors

Contact with permethrin
A flea product containing permethrin applied to a cat
Contact with a dog treated with permethrin
Some flea powders or collars containing permethrin for cats

How vets treat it

Antiparasitic treatment
Medication
Fluids or a drip

What the experts say

“If your cat has had contact with permethrin, wash it off immediately using warm water and dilute washing up liquid (if they will allow you to) and call your vet straight away. It’s likely that your cat will need to be admitted for treatment.”
— PDSA [1]

“Permethrin is highly toxic to cats, but it remains one of the most common causes of poisoning in cats worldwide. Permethrin is an insecticide used in some flea products for dogs and occasionally (in lower doses) in flea powders and collars for cats.”
— International Cat Care (iCatCare) [2]

If your pet is struggling to breathe, has collapsed, is having a seizure or can't stand up: go to the nearest vet now.

Not sure how serious it is?

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Common questions

What signs can permethrin poisoning cause in cats?

Signs can include drooling, twitching, tremors, wobbling, wide pupils, struggling to breathe and seizures or fits.^[1]

When should I contact a vet?

Contact your veterinary team immediately if you think your cat may have come into contact with permethrin or has been in contact with a dog treated with permethrin.^[2]

Can a dog flea product be a concern for my cat?

Permethrin is used in some flea products for dogs and is highly toxic to cats.^[1]^[2]

Sources

How this page was made: written with the help of AI from the sources below, then checked claim by claim against those sources. Urgency levels follow OkPaw’s fixed safety rules. It is guidance, not a diagnosis. How we write our pages