Get Profender if you can touch the cats. Or give each cat their dose orally - Pyrantel is easily administered, if you can restrain a cat for long enough to squirt the meds in the mouth.

You can also trap, fork - and do injectable wormer. That is what I have to do with some of my semi-ferals.

Let 'em skip a meal-
that always makes me eat whatever's on my plate!

Long boring story, but I recently learned about using food grade diatomaceous earth for internal parasites. It's rather cheap and safe, but very effective. It is a little funny tasting (tastes like a pond to me), so I'm not sure if they would reject it- you probably couldn't feed it in kibble either- it kind of mixes into watery stuff (and should be fed for a few days). I don't know if this could help you in any way, but figured I'd mention it as a possible solution that's rather safe- if you can find a way to get it into them! Best of luck.

forgot about DE!

I've used DE (use food grade, not swimming pool grade, which has been processed & chemicalized & who knows what else), & have been happy with it.

I sprinkled it on top of their feed, but you could mix it with canned food or yogurt.

I always get Dannon plain, (*not* low-fat) yogurt,
since cats don't need sugar & so forth.

This kind of yogurt comes in a white carton with blue letters, & the list of ingredients is "pasteurized milk".

I get the quart size.

Best luck!

I am and always was a great fan of DE. I use it monthly along with kelp meal mixed with of tuna for the cats. But -- they still have worms occasionally. Maybe, the DE needs to be in their food more often, but I hate to give the cats tuna too often and they won't eat anything else with it on there.

Still -- DE is great in the ears for mites and in the fur for fleas and ticks! We always bought it in 25# bags for the chickens when we had them and still have plenty, so we use it regularly.