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Pyrethrin

Pyrethrin and Pets

Find out if Pyrethrin is toxic to dogs and cats.

Dogs: Limited
Cats: Toxic

Think your pet ate something toxic?

Call ASPCA Animal Poison Control Center: (888) 426-4435 or view emergency guide

Pyrethrin is a natural insecticide derived from chrysanthemum flowers and is commonly found in flea sprays, shampoos, foggers, and garden insecticides. While it is marketed as a "natural" product, it is not safe for all pets. Cats are especially vulnerable to pyrethrin toxicity because their livers cannot break down the compound efficiently, which allows toxic levels to build quickly in the nervous system.

Exposure can occur when a cat is treated with a dog-only pyrethrin product, grooms a recently treated dog, comes into contact with sprayed surfaces, or inhales aerosol fumes. In dogs, toxicity is less common but can still happen with concentrated products, over-application, or ingestion. Signs of poisoning may appear within minutes to hours and include drooling, vomiting, tremors, muscle twitching, seizures, trouble walking, and difficulty breathing.

If you use pyrethrin products in your home or on your pets, always read the label carefully and only use cat-safe formulations on cats. Never apply dog flea or tick products to cats. Keep treated pets separated until products are fully dry, and ensure the area is well-ventilated during and after use. If you suspect any exposure, seek veterinary care immediately, as early treatment can be life-saving.

Is Pyrethrin Toxic to Dogs?

Dogs are less sensitive than cats, but concentrated pyrethrin products can still cause drooling, vomiting, tremors, or seizures—especially if misapplied or ingested.

Is Pyrethrin Toxic to Cats?

Pyrethrins are highly toxic to cats. Feline livers cannot efficiently metabolize these compounds, leading to rapid onset of tremors, seizures, and potentially life-threatening nervous system effects.

Active Ingredients

  • pyrethrin

Pest Targeted

  • fleas, ticks, mosquitoes, flies, moths, and other flying and crawling insects

Formulation

sprays, shampoos, dips, foggers, and topical spot-on treatments

Signal Word

caution

Application Area

indoor household surfaces, pet bedding, gardens, lawns, and directly on animals (dog-only formulations)

EPA Registration Number

EPA Reg. No. varies by product

Symptoms to Watch For

  • hypersalivation
  • vomiting
  • diarrhea
  • tremors
  • muscle twitching
  • seizures
  • ataxia
  • weakness
  • difficulty breathing
  • hypothermia
  • death (in severe cases)

What If My Pet Was Exposed to Pyrethrin?

If you suspect exposure, contact your veterinarian or a pet poison control center immediately. If a topical product was applied, bathe the animal with mild dish soap and lukewarm water. Do not induce vomiting unless instructed by a professional. Bring the product label to the vet.

Sources

Vet's Note

PetPilot provides general information for educational purposes. While we reference authoritative veterinary organizations, this page has not been individually reviewed by a veterinarian for your specific pet. Individual animals may react differently based on age, weight, breed, health conditions, and amount consumed. Always consult your veterinarian or a poison control center for personalized advice, especially if your pet is ill, injured, pregnant, nursing, or on medication.

Medical DisclaimerThe content on this page is not a substitute for professional veterinary diagnosis, treatment, or emergency care. If you suspect your pet has been exposed to something harmful, contact your veterinarian or call ASPCA Poison Control or Pet Poison Helpline immediately.