I'm one of the ones that have been buying the largest dog advantage and then measuring it according to weight for my cats. I do this year round because CA has a mild climate. Ever since I've been doing this, I've never had a flea problem.

I'm glad that you called your vets before you used anything and I hope that it will kill the fleas quickly. I don't know where you live but you may find that using this for at least most of the year will be better than just using it during the hotter months. Good luck.