My daughter was stricken with Bells Palsy right after giving birth, and her doctor gave her a B-12 every day for 2-3 weeks. We didn't know about methylcobalamin at that time--or maybe it was even available, I'm not sure.
She's fine now, but had one eye that would only partially close for quite a while so she wore a patch when she went to bed. Her son is 15 now.
Joan