Role of vitamin B12 in treating recurrent aphthous stomatitis: A review

Vitamin B12, a water-soluble vitamin, plays a vital role in the formation of hematopoietic stem cells and has been associated with oral mucosal diseases, mainly recurrent aphthous stomatitis (RAS). The latter is a debilitating condition, and B12 was proposed as a potential treatment given its role in regenerating oral mucosal tissue. There is conflicting evidence that B12 deficiency causes RAS. Five of the seven randomized controlled trials reviewed used the inactive form of B12 (cyanocobalamin) as intervention, while the other two used the active form (methylcobalamin). Of the latter two, buccal discs (500 μg B12) showed significant improvement and reduced perceived pain in 77% of the subjects, and submucosal injections showed a significant difference in pain, starting from the second day. Moreover, three studies administered vitamin B12 sublingually with different dosages, which revealed that the higher dose (1000 μg) achieved a significant reduction in outbreaks, number, and duration of ulcers, especially after six months. Multivitamins showed no difference in new RAS episodes and duration. Injectable B12 was compared with the oral form, and nearly 50% of the injection group reported a desired response by the eighth week. An ointment form (500 μg) showed a significant reduction in pain levels after two days of treatment. Based on the available literature, we suggest that a daily dose of 1000 μg of vitamin B12 sublingually for six months can be used to treat RAS. Nevertheless, this conclusion should be considered tentative due to the lack of high quality, large scale studies.