Benfotiamine helped, but did not cure my Peripheral Neuropathy, which was due to knee replacement surgery where the nerves are traumatized. PN was bad after surgery and slowly improved (I took a large vitamin stack). After ~12 months learned about benfotiamine and tried it. A little better. Then I called the company and the founder (a scientist) answered and explained how sometimes large doses were necessary at least to start with, and that toxicity was almost impossible. 1800mg a day helped - to an extent, then leveled off. I now take Drs. Best Benfotiamine 300 1x and alpha lipoic acid 300 + benfotiamine 150 8x. My neurologist approves of these supplements.
BTW, I once used r-lipoic acid to cure my loss of taste (taste only, not smell) from taking an anti-fungal rx (never again). EENT specialist gave me prednisone which helped nothing but gave me road rage and fluid retention. Google led me to ALA and RLA studies. Cured in days. EENT doctor refused to even look at the published research articles. It was a pleasure to tell him "Your services are no longer required."