mrs d.have you tried topamax for idiopathic PN? Mine turned out to be from a type of bromide/biomene/cleaner keep at very high level in my spa. I did not know for 18 years. it's a long story.....topamax has side effects[looking for nouns +a special type of memory effect] my dosage i 50mg ,three times a day.reduces pain50% +opoids.mine is feet to waist.Dr. gives slowly....PN ruined my life .nerologist,I saw 4 .bye mercer45