Benfotiamine, a form of B1 works well for neuropathy, and is quite safe.
I have been using benfotiamine for nearly a year, and my neurologist has checked my thiamine blood level three times.
Before I started BF, it was barely within low normal level. I started taking 3x 150mg capsules a day, and the next measurement was twice normal. Then I cut back to one per day, and it returned to the top end of normal. And all that time I had been taking a daily multivitanin that included 100% of the thiamine MDR.