Background: Recurrent Aphthous Stomatitis (RAS) is a kind of benign mouth ulceration. RAS is one of the most prevalent ulcers, affecting around 20% of the population. The goal of this study was to assess the effectiveness of probiotics on RAS. Materials and Procedures: A total of forty people were divided into two groups. For 7 days, 20 patients in Group 1 were given Bacillus coagulans (Sporolac) and Tetracycline capsules 250 mg (Resteclin) twice daily. For 7 days, Group 2 patients were given just Tetracycline capsules 250 mg (Resteclin) twice daily. At the baseline, 4th, and 7th days, pain, size, and average duration of the ulcer were assessed. For statistical Analysis, The Mann Whitney U test was used to compare the parameters between the two groups. Results: In just four days, the Probiotic group saw a substantial drop in all of the metrics.