dog licking leg

Question
I have a 9yr old Lab, he has been licking his rear left leg at the bottom by his paw for a few years now the vet has him on Synotic which is doing not a bit of good. I understand it's a habit, but I have to do something, is there a sock or something to put over it? I'm looking for some direction with this, some suggestions. Thank you Rich Ochs  

Answer
This is most likely a lick granuloma.  Synotic helps when the skin is very thin, but when it is thickened, it is infected with Staph bacteria in layers.  Long term antibiotic therapy with a fluoroquinolone type antibiotic sometimes helps along with the synotic.

I have had several dogs respond to Prozac therapy, as this is an obsessive-compulsive disorder. Because it is itchy, when the dog scratches and licks it, his brain releases endorphins, which make him feel good. Prozac interferes with this response.

My best and most favorite treatment for these is to laser ablate them.  That takes away the tissue, sterilizes the bacterial infection, and desensitizes the nerve endings, so the dog does not feel it anymore.  Ask your vet if he has a laser and if he doesn't, ask him to refer you to someone who does.