Also fleas or food allergies. I can always tell when my cats have fleas because I can see the tiny, black flea droppings on my bed sheets.

Bad cat food. Feed natural meat, not that canned stuff.

I may be overcautious because my cats are now elderly, but I would take them in for blood tests to check thyroid and other values just to be sure. Could be a lot of things.

Hmmm, not Frontline but I did apply Dermoscent on their backs a few months ago

Is it where you apply frontline? My cat lost his hair a few weeks ago exactly where I applied it.

Sorry to hear about your dog. I think that is not the case here because both cats have it at the same time

Cushings disease? That's what my dog with bald patches was just diagnosed with.

Two 7yo indoor cats, both with seasonal itchiness/environmental allergies. Cat #1 has been on Atopica for years with seasonal flare ups. Cat #2 (littermate) also often seasonally itchy but not to the point of overgrooming to injury like #1, so not on meds. Both have bald patch on their backs for a couple weeks - I don’t think ringworm because skin is not scaly or red. I do not see them grooming that area. What else could it be? I would be worried about thyroid if it weren’t for the fact that they both have the patches at same time. Do I chalk it up to allergies? Anyone btdt? Thanks