As far as tolerance goes, it seems to build slow with Neurontin and Lyrica, sort of like tramadol, but it takes even longer with N & L. I took it every day for a long time, per 2.8g a day prescription. I would take 18g to get really fucked up, plus an energy drink - Sobe No Fear or Rockstar - which really adds to the high, I'm not kidding. Then smoke herb about 2-2 1/2 hours, when the Neurontin or Lyrica is peaking, and that's easily as powerful a high as anything else, meaning most hard drugs. Whoops, got off topic, yay pot.
Anyhow, I stopped taking it altogether for about 4 or 5 months, then took it again, and it was great, but I don't remember how much I took. Then I didn't have it for another 6-8 months, and found 3 full bottles of 600mg Neurontin. I took like 8 or 9 grams several times and that got me off pretty well. Neurontin has lost some of its magic with me, having done it well over a hundred times in high doses. Lyrica is something new, and even better than Neurontin. I'm glad I have a script!