I always have a supply of "Droncit" on hand. These are very bitter tasting pills. My cats absolutely hate taking these pills but they are supposed to be really good. There is a liquid dewormer too but it is not as strong. Pekoe was the runt of the litter and was not nursing properly from birth. My vet thinks that is why she has had a hard time getting rid of the worms. She is doing great now and is extremely affectionate and healthy!