I have several cats that never go outside. Only time I take them outdoors is for vet visits.
Is it still necessary for flea and tick treatment?
Pets Stack Exchange is a question and answer site for pet owners, caretakers, breeders, veterinarians, and trainers. It only takes a minute to sign up.Sign up to join this community
That's a judgement call. They may be indoor-only critters, but you aren't, and your guests aren't, and it's not impossible for fleas or ticks to be carried indoors on you or your clothing... just as a mosquito carrying a disease might get through an open door or your screens.
On the other hand, some of the treatments may put some minor stress on the cats' systems. So it's a matter of trading off a known minor risk against a low probability but possibly more serious risk. It's also a matter of how willing you are to deal with the problem should it arise.
Recommendation: Ask your vet. They should know what the local risks are and be able to trade them off against benefits. My vet, in my part of the world, recommends a yearly heartworm treatment but doesn't think my indoor cats need flea/tick collars or drops. Your vet may have other recommendations based on their understanding of local conditions and the latest studies.
(My cats have been supervising as I type this message, and seem to approve.)