Hi Guys,
I am another Comfortis convert. Had limited success with any spot on treatments, seemed to last 3 weeks at best. Gave my boy one dose (was recommended by my vet to give with dinner/meal) and that was it! Bye bye fleas. I gave him the one dose, easily 3 months ago and haven't re dosed since, because despite our extremely wet, hot summer, he hasn't had a single flea on him!