Multivitamin therapy for recurrent aphthous stomatitis: a randomized, double-masked, placebo-controlled trial.

Randomized, double-masked, placebo-controlled trial in adults 18 years and older with idiopathic minor recurrent aphthous stomatitis, defined as at least three episodes in the prior 12 months. Participants were recruited from Hartford County, Connecticut, and the study was conducted at the University of Connecticut Health Center in Farmington; the multivitamin arm included 83 participants.

Participants in the active arm received one oral generic multivitamin capsule daily for 365 days. The supplement provided the U.S. reference daily intake of vitamins A, B1, B2, B3, B5, B6, B9, B12, C, D, and E, and contained no iron or calcium; placebo was given in the comparator arm.

Daily multivitamin supplementation did not reduce recurrent aphthous stomatitis frequency or duration, so routine prophylactic use is not supported. The number of new episodes over 1 year was similar in the multivitamin and placebo groups, 4.19 (4.74) versus 4.60 (4.58), with a treatment effect p value of .69 and treatment-by-group interaction p value of .40. Episode duration was also similar, 8.66 (4.60) days versus 8.99 (5.22) days. Pain scores, normalcy of diet during episodes, and adverse events were not meaningfully different; none were reported as adverse events.

Single-center trial in a relatively specific population with idiopathic minor RAS, which limits generalizability. Several symptom outcomes were based on fewer analyzed participants or episode-level observations than the randomized arm size, and no benefit was seen despite a full year of follow-up. Baseline vitamin status appeared adequate, which may reduce applicability to deficient populations.