Shayla's on Revolution as well. However, Revolution is proven to be more effective to cats than dogs, since it is applied to the animal's skin and cats groom themselves with their tongue and it will get in their internal systems, but for dogs most of the medication just stays on the skin.
My vet recommands taking monthly pills (I forgot the name) to kill worm and flea cycles. Shayla had a tick on her last year, although she was on Revolution the whole time. I'm going to switch her to pills this year. Hope that helps.