The good news is that if prediabet'es is the cause of your nerve damage it is fully reversable, through a sensible diet and exercise, my PN was caused through prediabetes & i was low in b12 and now i am nearly healed.
I have seen many posts were people using Neurotin have stacked on the weight, i did try it first up myself but couldn't tolerant the med, but if i would really work at keeping your blood sugars to good levels, Glentaj is spot on. trouble is a lot of doc's don't think that prediabetes can cause PN, they think that you have to be a full blown diabetic for many years before any nerve damage happens which is not correct, depends on the individual, some full blown diabetic people don't get any nerve damage or it takes years but there is ever increasing evidence that SOME can get nerve damage in the early stages of diabetes when it's at borderline diabetes stage.
good luck
Brian