Purpose: To determine both the efficacy and safety of the topical application of 50 mg penicillin G potassium troches (Cankercillin) in the treatment of minor recurrent aphthous stomatitis (RAS).
Study design: The investigation used a phase 2 double-blind, randomized placebo-controlled trial with a no-treatment arm. Subjects with minor aphthous ulcers of duration <48 hours were followed for 1 week. The primary endpoint for efficacy was time (days) to complete ulcer resolution, and the secondary endpoint was time (days) to complete pain relief.
Results: Thirty-one, 33, and 36 subjects were randomized to the active treatment, placebo, and no-treatment arms, respectively. Baseline findings were heterogeneous across arms. Subjects who received penicillin G treatment had complete ulcer healing and pain relief significantly earlier than those in the placebo and no-treatment arms. No allergic reactions were observed.
Conclusions: Topical penicillin G, by mechanisms which remain unclear, reduces the time of healing and pain relief of minor aphthous ulcers with minimal safety concerns. Larger phase 3 studies are necessary to confirm these findings.