Topical Clonazepam in Stomatodynia: A Controlled Study

Stomatodynia is caracterized by burning pain in the oral mucosa. There are no knowning cause nor recognized treatment. Objectives:The purpose of this study was to evaluate the efficacity of the topical use of clonazepam in the control of stomatodynia symptoms. Methods:In this double-blind, randomized and multicenter investigation, each of 48 patients with stomatodynia was assigned to suck 1 mg of clonazepam or placebo and to hold their saliva near the pain sites within the mouth without swallowing for three minutes before spiting. They repeat this administration three times a day for 15 days. The intensity of pain was evaluated by a ten grades numeric scale before the first administration and after 15 days. Dosages of clonazepam blood levels were performed in 4 patients who had received the treatment with the topical clonazepam for more than 15 days. Results:Two weeks after the beginning of treatment, the decrease in pain intensity scores amonted 2.4±2.9 in the clonazepam group and 0.65±2.0 in the placebo group. The decrease was significantly more prononced in the clonazepam than in the placebo group (p=0.014). Blood level dosages showe that after 15 days of topical treatment the concentration of blood clonazepam was below the theshold values observed with systemic administration for antileptic therapy. Conclusion:The hypothesis that clonazepam acts locally to disrupt the neuropathic mechanism that underlies stomatodynia is proposed.