Can anything ease extreme neuropathic pain?

My husband went to a doctor in mid April with pain in his feet.  At that time he was diagnosed with Type 2 Diabetes, high blood pressure and thyroid issues.  Since that time, he has brought his glucose levels down to normal range (4-7) and remains on Metformin, Crestor, Lyrica, Synthroid and sometimes Gluconorm.  Although his levels including his blood pressure have dropped to normal range, his feet continue to feel like they are in a vise.  Sometimes it changes so they barely hurt at all but those periods are less frequent as time passes.  Currently, he is in incredible pain almost continually and gets no relief.  There are also episodes of tingling, burning and sensitive skin in his arms as well as his feet and calves.  It feels best when he is standing although that is painful too just less so.   Tylenol 3's do nothing for him and he is in agony.  MRI has shown some minor "delineation in his spinal sheath"?   and we currently await "another" neurologist to look at the results to determine if it could possibly be the onset of MS or whether it is possible that it may be diabetes related.  What can he do for the pain?  He is going crazy.....