Hi,

You might try fish oil:

Frontiers | Long-Chain Omega-3 Fatty Acids Supplementation Accelerates Nerve Regeneration and Prevents Neuropathic Pain Behavior in Mice | Pharmacology

You will might also be interested in reading the thread on Resveratrol in the main forum for PN.

Resveratrol

I have been taking both fish oil and resveratrol for three months, unfortunately to no noticeable effect.