I have Trigeminal Neuralgia. It's really tough to find out what works for you, medicine-wise.
I see you found the T.N. board, I hope you can find some answers there.
For my 2 cents worth, I know mine's triggered mainly by birth control (Depo Provera was the worst, combination birth control pill wasn't much better). I now have a Mirena, and that seems to have resolved the mess of my cranial nerve drastically - perhaps by regulating my hormones?
I also take Clonazepam for Burning Mouth Syndrome (low dose, .75 mg daily) and Cesamet for my neuralgia pain (not T.N.) so I'm not sure if perhaps either of these medications can be thanked for keeping my acute type 1 T.N. attacks (the sharp, stabbing, throbbing, pulsing pain in the head) under control/non-existent.
I honestly believe the hormones are more so to blame in my case, and keeping them 'regulated' as such is why I'm not having such dreadful attacks now.