Hi Mark,
Are you only taking Neurontin? If so, maybe add on oxycodone if it has helped in the past or just be honest with your doc that Neurontin is not cutting it anymore.

I find that taking a combination of meds for neuropathy is what has helped me the most but, I also have several other pain issues like migraines, cervical disc issues etc but neuropathy is my worst, most severe pain.

I take a combo of hydrocodone 10/325 (10 mg dose that is combined with 325mg of acetominaphen) and I take Lyrica, but a low dose(100mg daily).
My doc trusts me and let's me add in other meds as I need them, oxycodone in 5 mg doses that I can add on when pain flares. Also, I have Soma, a muscle relaxer and lorazepam, a tranquilizer. I only learned that helped when given to me to cope when my Father was home with us on hospice. I was actually surprised. My pain doc said it works because stress makes pain worse.

As a last resort, at least for me, I take amitriptiline (Elavil), which is actually an antidepressant but also used for pain. It literally knocks me out. I only use it when my pain is so bad I cannot function at all. That is just me though, I know folks who take it daily and function normally, I can barely form a sentence so it is for emergencies.

Even though it is only topical, there are various forms of lidocaine....patches, creams, etc.

I wish you the best.
D.