Ok. I have inside only cats, and outside only cats. I can easily catch and treat 2 of the outside cats, but the rest are adopted ferals, so the catnip idea is a good one for them if needed.
I will be sure to pick some catnip and dry it so I can mix it in their food sometimes to help keep them worm free.
I have plenty of catnip growing in the yard all summer! But don't want to hook the inside cats on anything unnecessary. (I have only given them the catnip a few times.)
Thanks for the great info, Hissy!