I adopted 5 FIV+ cats recently and I wasn't told that they might develop balding spots. Have you been told that FIV+ cats get balding spots? One of them, Dude, has a few on his head, but he's about 15 and pretty beaten up looking so I thought it was just part of the way he looks. Have you talked to your vet? Hair loss can be caused by a skin condition - does his skin look okay? Is he pulling his fur out? I have one cat that does that and she is on anti-anxiety medication. Sorry that I don't know of an ointment that will help.