1. Contact your veterinarian immediately and take your pet to your veterinarian as soon as possible.
  2. Early, aggressive decontamination may reduce absorption. Asymptomatic cats should be bathed gently in lukewarm tap water with a mild dishwashing detergent applied at the site of application. This should then be rinsed off thoroughly. Excitement can precipitate clinical signs, so bathing should only be undertaken where this does not cause excessive stress. DO NOT ATTEMPT TO BATH AN ANIMAL THAT IS SEIZURING – THERE IS A HIGH RISK OF BEING BITTEN OR SCRATCHED.
  3. If possible, provide the package or package insert of the product applied to your veterinarian.


Pyrethrins, pyrethrum, permethrin




Onset of clinical signs is usually within 1-3 hours of application, but may be delayed up to 72 hours.

  • Anxiety
  • Dilated pupils (mydriasis)
  • Hypersalivation
  • Vomiting
  • Uncoordinated gait (ataxia)
  • Hypersensitivity to touch (hyperaesthesia)
  • Markedly increased heart rate (tachycardia)
  • Tremors
  • Respiratory distress
  • Muscle twitching
  • Seizures
  • Hyperthermia


Pyrethroids act on sodium channels in nerve endings, leading to excitation and repetitive firing of nerve cells in the central nervous system, especially in the spinal cord. This leads to excitement of the nervous system.


Pyrethroids such as permethrin are synthetic pyrethrins found in some insecticides and anti-parasiticides including spot-on preparations for dogs, pour-ons, powders, sprays, shampoos, dips, foggers and gels. Because these products are applied to the skin, ingestion can occur via grooming (for example, an untreated cat may groom the product off a permethrin-treated dog). Tick products for dogs frequently contain permethrin. Permethrin toxicity in cats typically occurs when a product registered for use in dogs is applied to a cat.


Veterinary care may involve medication to control seizures and muscle relaxants. In severe cases, prolonged general anaesthesia and ventilation may be required.



BSAVA (2012) BSAVA/VPIS Guide to Common Canine and Feline Poisons. Gloucester: BSAVA.