N-acetylcysteine versus chlorhexidine in treatment of aphthous ulcers: a preliminary clinical trial.

Introduction: This study sought to assess the efficacy of N-acetyl cysteine (NAC) in the treatment of recurrent aphthous stomatitis (RAS).

Methods: Fifty-eight patients, aged 28 ± 9.7 years, presented with clinically diagnosed RAS to two oral medicine centers. They were assigned randomly to a single application of either NAC (200 mg dissolved in water,  = 38) or 0.12% chlorhexidine digluconate (CHX,  = 20) mouthwashes for 30 seconds. Pain was measured using a Visual Analog Scale (VAS). The size of the ulcer was measured through its greatest dimension using a periodontal probe. These two measurements were taken pre-application (day 1) and 2nd, 4th, and 6th day post-application. Average time (in days) until complete healing was assessed.

Results: Of all participants, 33 (57%) were females; 34 (59%) married; 29 (50%) reported a family history of aphthae; and 51 (88%) were affected with minor RAS. There were greater improvement in pain from day 1 with NAC on the second day (-3.0 ± 2.0 versus -1.8 ± 1.9;  = .028) and on the fourth day (-5.0 ± 2.6 versus -3.4 ± 2.7;  = .041). The differences with regard to the change in ulcer size and average healing time were not significant between NAC and CHX.

Conclusion: Single application of NAC results in a clinically significant reduction of RAS-associated pain within one day of application and is more effective than CHX.