I have a round rash that is not responding to ringworm or impetigo meds...help?!?

I have had this rash since November, so that's 7 months and I went to my pcp, she first said ringworm, gave me antifungal cream, did not respond. Then she said it was impetigo, gave me muciprin (sp?) did not work.
It is perfectly round, very itchy, weeps when first layer of skin falls off, and is anywhere between pinkish to reddish, depending on when I look at it. Also it is the size of a nickel, and is on my chest. I am very worried that it is not responding to meds and I've had it so long.
Doctor said that she did not think it was cancerous or dangerous. Not spreading at all. But, she was wrong about the first two diagnosies so who knows.
I can't get into a dermatologist for like 3 months! And I was just wondering if anyone had any clue what this might be.
So, if you have any suggestions, that would be greatly appreciated!

See if the doctor will do a culture and sensitivity on this.

Are you in a Lyme endemic area? Could this be a somewhat unusual/chronic presentation of an chronic erythema migrans rash?

It is definitely a tricky condition. I highly recommend getting African Black Soap to use on your problem. You can purchase on Ebay. I got mine at a local farmers market. for a skin problem I had. The soap looks kind of like a brown crumbly oatmeal texture. I used it twice a day for a few weeks and it has taken care of my problem. You take a wet cloth and wipe it over the soap and apply to the area and it lathers up. I leave it sit on for about 3-5 minutes and wash off. When it is dry I also apply shea butter (100 %) on area too. I am stoked after using medications that did not work on my problem, maybe this will work for you. Good luck.