Flea Medicine Safety Question

Are the topical flea medications that you get at vet offices safe to use on an older cat around a 5 month old kitten? The kitten wouldn't be having it applied. It'd be my older bigger guy that needs the version for over 9 lbs. The kitten was 7.65 lbs last I checked. I was just feeling concerned if they played together and the kitten touched the spot if it could be worrisome?

I'm not 100% sure but personally I'd keep them apart for a while (say 30 min to 1 hr) just to be safe. When I apply it on mine (both adults) I tie a little bandana around their necks as a way to keep them from licking the spot. I take the bandana off after about an hour (some topical products will say make sure they don't get to the spot for 30 minutes, if I remember correctly?).

It's safe The topical medicine dries pretty quickly but if you wanted to, you can keep the two cats separate for 15 minutes or so. Try to discourage the one cat from licking the application area until it dries. The kitten accidentally touching the dry application spot won't be harmed at all.