We use Revolution and it has always worked well. I like that it is dished by weight. The issue is not just fleas - it is also heartworm protection that needs to be done. If we are hiking I use a Seresto that I keep in a zip lock bag the rest of the time.
__________________ .   Cali  , and Cali's keeper and staff, Jay No, not a "mini" Yorkie - She loves to motor in her Mini Cooper car  |