In order to save money, people will sometimes use dog flea products on their cats. Unfortunately, this can have costly and potentially deadly repercussions.
Many flea products, particularly over-the-counter brands, contain a drug formulated from the Chrysanthemum flower called Pyrethrin; there is also the stronger synthetic version, Permethrin. These chemicals work by paralyzing the insects' nervous systems and kill fleas through both ingestion and direct contact.
When dosed incorrectly, flea products containing these chemicals can be deadly to cats. This can happen from skin absorption through topical application or ingestion through licking the site of application.
Permethrin-based insecticides have a much greater potential for toxicity than Pyrethrin products and usually are labeled "for use in dogs only." Cats can tolerate Permethrin at a concentration of 2 percent while most dog products contain it at a level of 45 percent to 65 percent.
Signs of toxicity will usually take place within six hours of insecticide application or ingestion. Symptoms include salivation, seizures, depression, difficulty breathing, lethargy, ataxia (poor coordination), muscle tremors, vomiting and hyperthermia or hypothermia (high or low temperature). These signs can occur with topical application of the flea control product alone but are accelerated if the cat also happens to lick the product.
Go to your veterinarian immediately if you suspect this type of toxicity has occurred. Treatment will include bathing to remove as much of the insecticide as possible. IV fluids will be given to provide supportive care.
Medication will be administered as needed to control the seizures and muscle tremors. Hospitalization is usually needed for 24-48 hours and there may be some residual muscle tremors. Even with proper treatment, some patients die or are euthanized.
The best way to avoid this problem is to not use products containing Pyrethrin or Permethrin. If you do use products containing these chemicals, follow the dosing instructions very carefully.
If you use these products on your dog and also own a cat, keep your pets separated for at least four hours following application. If you suspect your cat is having a reaction to one of these chemicals, take him or her for veterinary care immediately.
Julie Damron is a veterinarian at Sierra Veterinary Clinic. Contact her at .