Vlad is missing fur! Please help...

My four year-old indoor cat, Vlad is suddenly missing fur in two places.

Behind his ear he has a balde spot and on his back there is a patch. The patch on his back looks irritated and red. The other cats are fine. None of my cats go out. I haven't seen any fleas, but I haven't had anyone on Advantage since January?

Any ideas before I go to the vet?

Thanks in advance.

It could be anything from an allergic reaction to ringworm. Your best bet it to get him to a vet and find out what it is so you can treat it.

Thanks.

We have an appointment for tomorrow afternoon. I'll keep it posted.

Thanks.