Just a heads up. Frontline and Frontline Plus are no longer working for me in preventing fleas and ticks. I've switched to putting half the dogs (Yogi) on K9-Advantix and the other half on Advantage, and so far, so good. Please be mindful that the effectiveness of some of these flea-tick-etc. (in my case, Frontline) products appears to be diminishing. I know of others who've had the same problem. I don't know if there's been a change in the formulation or if the bigs have developed a resistance, but I would advise everyone to keep an eye out and switch in a second if what they're using doesn't appear to be working.