I live in Florida and I have a toy poodle who gets fleas pretty badly. When fleas first became a problem, we used Advantix on him and the stuff worked like a charm. We could go for months on one application - sometimes forgetting to re-apply it. Then Advantix II came out. The results have been disastrous. The first version worked within hours or a couple of days of the application, and then kept right on working long after the manufacture's suggested reapplication time. This new stuff seems like it takes forever to work, and then it only lasts a few weeks. We were told by the company to give it up to four weeks to work. Four weeks? What are you supposed to do in the mean time when your dog is scratching and being driven crazy? I need an alternative. I don't want to use this stuff anymore. I wish they never changed it.