As long as you have your kitties' weight, I am sure you can just pick up the stuff at the vet. There is Frontline and Revolution...I am not sure which is best or which one kills fleas and worms both. Best to play it safe, I think. They each may need a second dose to catch any eggs that hatch.
"When I think of Mick Jagger still singing that he can't get any satisfaction in over forty years of being in the Rolling Stones, I have to conclude that he's either lying or not all that bright." -- Henry Rollins