There is a study on PubMed where 10mg a day of biotin helped a patient with burning mouth syndrome.

I've been using 7,500mcg (7.5mg) off and on in bursts of 3 months or so on, then off...for 2 years now. I find it very helpful for my nerve pain. It is very good for strengthening the skin and hair too. I get mine at Puritan's Pride.

Biotin uses the same transporter as alpha lipoic acid. So if you take that supplement also, space them about 12 hrs apart.

I can't really comment on these mega doses however in the 100's of mg area. I haven't see papers on that yet.

But here is the updated monograph from Linus Pauling Institute:
http://lpi.oregonstate.edu/mic/vitamins/biotin

It has a comment on the MS use so scroll down to "disease treatment" section.
There are some really helpful schematic diagrams for
the biochemical importance and uses of biotin on this monograph.