When I was DXed, I was handed a prescription for 300 mg. capsules, with instructions for titrating up to 900 mg./day over 3 days.
http://www.ncbi.nlm.nih.gov/pubmed/12637113

I thought this was high also, so after some discussion, the neurologist agreed to rewrite the scrip for 100 mg capsules, taken at night as needed, and I would titrate up if necessary. AFAIK, 100 mg is the smallest dose available/made.

This amount was sufficient to address the burning pain I was having at the time, and I only took it a few times before learning of and starting R-Lipoic Acid (RLA). The RLA worked extremely well for me, and I haven't needed any gabapentin since (over a year). I read someplace online (can't find the link ) that the sooner RLA is started, the sooner and better it works. Others' results vary.

Doc