Sixty patients with Bell's palsy were included in an open randomized trial. Patients were assigned into three treatment groups: steroid (group 1), methylcobalamin (group 2) and methylcobalamin + steroid (group 3). Comparison between the three groups was based on the number of days needed to attain full recovery, facial nerve scores, and improvement of concomitant symptoms. The time required for complete recovery of facial nerve function was significantly shorter ( p < 0.001) in the methylcobalamin (mean of 1.95 +/- 0.51 weeks) and methylcobalamin plus steroid groups (mean of 2.05 +/- 1.23 weeks) than in the steroid group (mean of 9.60 +/- 7.79 weeks). The facial nerve score after 1-3 weeks of treatment was significantly more severe (p < 0.001) in the steroid group compared to the methylcobalamin and methylcobalamin plus steroid groups. The improvement of concomitant symptoms was better in the methylcobalamin treated groups than the group treated with steroid alone.[1]

1.  Jalaludin, M.A., Methylcobalamin treatment of Bell's palsy. Methods Find Exp Clin Pharmacol, 1995. 17(8): p. 539-44.