We don't have fleas, I used Advantge last year. May through Oct. Inside only cats, so I try not to use to much stuff. ANYway, I am lookin for a natural product to use, I tried a product at found at Wal-mart, Sergeant's Gold, but it made a scab on the cats backs, I don't know if it was the product that had dried, or the skin that had been burned. They also quit eating for about 4 days. It's good they are fat. We have had a cut in $$ in my house and thats why I am tring another product, Advantge is about $70 per box and I have 4 cats. You can do the math. And yes we will drag fleas in the house, it just is what happens.