Use of Biotin

I am an 85-year-old male with alcohol-induced peripheral neuropathy, diagnosed 10 years ago. My symptoms are painless numbness in both feet initially but extending up both legs to mid-calf over the past two years. I have stopped alcohol use and take a super B vitamin along with 300 mg of stabilized R-lipoic acid (Biotin optimizer) daily, which seems to lessen the numbness intensity. I have read encouraging things about Biotin in this discussion group, and my physician approves trying it. It comes in 500, 1,000 and 10,000 mg doses. Should I start with 500 and for how long to experiment before increasing the dose?