I agree with Audrey, Biotin is good but start at a low concentration then increase. Make sure to up your water intake as well, biotin made my face go crazy but that was b/c I had little water in my diet.

Also this stuff mega-tek (yes it is for horses) helped my mom out with a bald spot due to a horrid relaxer. It smells like coconut and it is pretty inexpensive and you can get it from a local feed store.

http://www.amazon.com/Mega-Tek-Rebuilder-Hoof-Mane-Horse/dp/B001D0H248

massage that area to encourage circulation