I think my dog has a skin p..

My dog has been scratching at the upper inside part of his right front leg with his teeth and licking one particular patch lately. I noticed that the fur was all gone from the area and the skin beneath has turned very red. He won't stop licking it, and when I accidentally brushed against the furless partch he growled so I'm assuming it is painful to touch. I made an appointment with his vet but they're booked for quite a while, and I'm worried about what could possibly be wrong with him and keeping him from irritating the spot any more.

Does anyone have any idea what could be wrong? How can I help/temporarily relieve any pain/itching? And how can I keep him from licking the patch?

He just turned 9 years old (december 28th :]), and he is otherwise very healthy. He is a mutt.

Any answers/advice would be great! I just can't stand seeing him in pain! I could probably upload pictures of the patch if that would help at all, just let me know.

The only things I can think of are mange or psoriasis. They can pick up mange from other animals. It could be fleas too. Put him over a white towel and brush him. If you see any black specks on the towel, drop some water on them. If they turn red and smear it is flea dirt and he might have fleas.

One thing to note: My cat had this same problem a month ago. I didn't know what it was but I now think it was really dry skin. I started giving him Omega-3 rich foods and treats (salmon oil, coconut oil, olive oil, etc) and he no longer has this problem. But there are a lot of skin conditions out there that can cause that balding and itching. Since the vet is booked, I would call them and ask them what the benedryl dose is for a dog. You can give a dog childrens liquid benedryl, but I don't know the dose anymore...the vet will. Maybe they will give you the dose over the phone..if not look it up on the Internet. This will help the itching and pain until you get him to the vet. Hope your doggy gets better!