Our cat rescue group and hundreds of customers (previously sold through eBay) have used Frontline Plus for Dogs on cats. You will be receiving the DOG FORMULA of Frontline Plus (large dog tube) and a kit and instructions that enables you to measure out the correct dosages for each weight/type of animal.
All Frontline Plus for dogs contains 9.8% Fipronil and 8.8% Methoprene. The Frontline Plus for cats contains the same amount of Fipronil (9.8%) and 11.8% Methoprene which is more than in the dog formula. Hence, we have used the dog formula safely on cats.
In our rescue group and the low-cost spay/neuter clinic we work with, we all use the large dog tubes and “dose down” to save money. We care deeply about our cats and would never use anything that could harm them. We rescued over 600 cats in 2010!
The cat formula contains a higher concentration of Methoprene than does the dog formula, so it’s fine to use the dog formula on cats. I was told that cats have fewer pores per square inch of skin than do dogs and therefore the larger amount of Methoprene. Though, it doesn’t explain why the Fipronil is not stronger too. Go figure.
What I do know is that we have treated thousands of cats with Frontline Plus Dog formula with no ill side-effects and with HUGE cost savings. If you do not feel comfortable using a slightly different formula, you can order Advantage II kits. The Advantage II product is exactly the same formula for dogs and cats!