I was prescribed gabapentin off label by my CFS doc as he was experimenting with his patients with some of Goldstein's recommendations. When I first used it I loved it and thought I was going to be one of these overnight recoveries that I read about in articles written by Dr. Goldstein. I just felt close to 100% on it, but then it wore off after 5 days. I stayed on it for weeks, and upped the dose hoping for a comeback, but unfortunately it was now like taking a sugar pill. I had a break from it them tried it again, and got the great effect again, but now only for about 2 days. For a few years there I used it by going off and on - 2 weeks off 2 days on.
I tried something similar, I think valpoic acid and also the next generation of gabapentin (forget its name) which was marketed more as pain signal blocker. No great boost to well-being but it was a good sleep aid.