2 Ways Cats Get Sick from Dog Flea & Tick Products

Posted on May 16, 2016 under Cat Topics

Dog-specific flea and tick medications that are dangerous for cats.

By Dr. Fiona Caldwell, a veterinarian and writer for Pets Best, a U.S. pet insurance agency since 2005.

Flea and tick prevention is a crucial part of a healthy summertime routine for both cats and dogs. But, did you know that some dog-specific flea and tick medications are actually toxic to cats? In a Pets Best nationwide survey, veterinarians reported it as the 4th most common toxicity they treat cats for (March 2015).

Two common ways cats get sick from flea and tick products for dogs are:

1) The pet owner will apply a dog-only product to the cat, not realizing it is dangerous.

2) The pet owner will apply it to their dog as directed but soon after the application, the dog will come in close contact to the cat.

Which Flea and Tick Products Are Safe (and Not Safe) for Cats?

Topical products:

Topical, or ‘Spot-on’ treatments, are some of the most popular products available. Not all topicals are the same and some can be very toxic to cats.

Permethrin, whose name brands include Vectra 3D, K9 Advantix, Bio Spot-on, some Hartz products and many others. All of these are extremely toxic to cats.

Fipronil, name brand is Frontline. This product is available over the counter and is safe for cats when the cat-specific product is purchased.

Selamectin, name brand Revolution. This is available by veterinary prescription only and is very safe for cats.

Imidacloprid, name brand Advantage. This is available over the counter, and again be sure you’re using the cat version of the drug, not the dog version.

Metaflumizone, brand name ProMeris (no longer available). This product was formulated with Amitraz which is toxic to cats.

Flea and tick collars:

Most dog flea and tick collars contain permethrins or organophosphates and work by repelling insects. These are very toxic to cats and in some cases can be fatal.

Tick-only preventative collars, such as Scalibor (Deltamethrin), or Preventic (Amitraz) are meant for use on dogs only and are toxic to cats.

Oral Prescription Medications:

All oral preventatives are available by veterinary prescription only. Some oral medications are adulticides, such as Capstar (Nitenpyram) or Comfortis (Spinosad). These are both safe products in cats.

Other oral products work on different flea life stages, and can include such brands as Bravecto (Fluralaner, this is not labeled for use in cats) and Program (Lufenuron, which is labeled for safe use in cats).

What’s The Bottom Line?

Always use a product intended for cats and use it as directed on the label.

Just because the product is available in cat and dog formulations doesn’t mean they are interchangeable. Remember the small dog dose may be very different from the cat dose. Even if those animals have the same body size!

In general, it is a good idea to consult professional veterinary help with choosing a flea or tick product. Not only will your veterinarian direct you to a safe product, most prescription products are also more effective than over the counter solutions.