Bio Spot!! This spring was the 2nd summer we used bio-spot on our 9 dogs and 4 cats. We had planned on treating them before fleas got active this spring, but found a few sooner then expected, so we treated them immediately. Within two weeks, no fleas. VERY, very few throughout the entire summer on ANY of the animals. I'm in love with this stuff, especially with all our pets being indoors. (yes, it's a zoo 'round here). (Well, the dogs go in and out through the dog door and yes, it's a fenced back yard). *grin* A lot of our pets were rescues, not placeable in other homes because of health problems. So we had been leery about using treatments like this. However, we haven't had any side effects or problems at all with Bio-spot. Love it, love it, love it! Hey, ya know what? I love that stuff!