The rescue agencies that have helped us rescue, foster, socialize and place some of our feral rescues said essentially the same thing. Both piperazine (branded as D-Worm liquid in most pet stores) and pyrantel pamoate will treat for roundworms and the like. Drontal or a generic alternative includes praziquantel in addition to pyrantel pamoate which will also take care of tapeworms, which are gross to humans but not as harmful to cats as other parasites. D-Worm will be easier to mix with food, and will get rid of roundworms. When we first rescued our last litter at about 5-6 weeks old, we treated first with D-Worm (fecals were all negative after that), and then when they got a bit older generic Drontal to also take care of the tapeworms. They really liked the D-Worm mixed with their food. Used Pill Pockets to administer the generic Drontal.
A socialized feral female who we rescued as a breeding adult is now so sweet I can do almost anything to her now except pick her up. When we first found her, she wouldn't let anyone near her. She'd cry for food, and then back away and hiss and growl. I really didn't think she would be socialized and after we trapped her and got her fixed brought her inside, first in a large dog crate and then in a small cat-proof room on a 2-week trial basis, thinking we'd eventually release her. Amazing what food and care will do because now she's tamer than some of our other cats who have lived indoors with us most of their lives. So administering spot on treatments (we use Revolution b/c it also prevents worms) is not an issue with her. However, one of my late stage kittens and another now-adult cat who we rescued as a feral kitten are impossible to handle, and we have to really plan out how we can treat them every month. The kitten isn't too bad because it doesn't require picking him up, but Francine, the now-adult cat who never fully socialized despite our best efforts, is a chore. We manage to do it but it's not as simple as finding cat and administering spot on. So I've been looking at the oral alternatives. Capstar supposedly works really well in conjunction with Program--Capstar to immediately kill adult fleas and Program for month-long flea control.
