Jack,
many doctors prescribe cymbalta for nerve pain. It is also an anti-depressant. It was originally intended for people with diabetic peripheral neuropathic pain. People that have used it have found that it does help with nerve pain. Hope you have tried it since it does not seem to have the same side effects of the other drugs prescribed for nerve pain, neurontin, lyrica, and topamax. Neurontin and topamax both seem to cause brain fog, (memory loss) and other undesirable side effects.
I have used topamax though and have found some pain relief with its use. It does take a few weeks though to get through the brain fog, hence the nickname, dopamax. Each person seems to have different reactions to these type drugs, so you really cannot go by anyone person's reaction to this drug. You have to try it yourself, since what I might find tolerable, you find intolerable. Also, neurontin, topamax and lyrica ( another new drug very similar to neurontin.) were originally prescribe for epileptics.