There is a series of books by Robert Cochran, a pain doctor, now retired, who had good results with those drugs in chronic pain patients. I have read his work and as I understand it, chronic pain is different from chronic illness or disease in that the pain is either unrelated or disproportionate to the physical cause. PN is a known cause of severe pain, and so does not fall directly into this category. He further found a link between chronic pain, childhood abuse, and bipolar disorder.

His treatment of such patients with these drugs, he later added opiates, preferring methadone, had often stunning success, but there were really no long term studies to see how these people did after several years. Also, as the doctor retired many of his patients were unable to find doctors willing to continue the therapy.

Mrs. D.'s warnings are quite apt. A careful cost-benefit analysis has to be done by doctor and patient before starting potentially addictive medications, including thinking about what happens if you have to switch doctors due to retirement, death, relocation, or insurance. Anything too unconventional could be difficult to continue.