Efficacy of Oral Mucoadhesive N-Acetylcysteine Tablets in Treatment of Recurrent Aphthous Stomatitis: A Randomized Double-Blind, Placebo-Controlled Clinical Trial.

Objectives: This study aimed to assess the efficacy of oral mucoadhesive N-acetylcysteine (NAC) tablets for treatment of recurrent aphthous stomatitis (RAS). Materials and Methods: Forty-nine patients with RAS were randomized to receive mucoadhesive NAC tablets (n=25) or placebo (n=24). Tablets were prescribed three times a day for 7 days in each group. Pain intensity was evaluated with visual analog scale (VAS) three times a day from day 1 to day 7. Also, patients were clinically examined on days 0 (before entering the study), 3, 5, and 7 using a metal caliper to measure the diameter of the lesions. The data were statistically analyzed and P<0.05 was considered statistically significant. Results: Regarding the VAS score, all participants in the treatment group showed complete recovery on day 7 (P<0.01). Also, the diameter of the lesions was significantly smaller in the treatment group than the placebo group at the end of the study (P<0.001). Conclusion: The results of this clinical trial showed for the first time that mucoadhesive NAC tablets can significantly decrease pain and the diameter of RAS lesions without any systemic complications.