ABSTRACT Background and Objective: Oxygen therapy has been proven to be beneficial in the treatment and healing of chronic wounds. Oxygenated mouthwash could help in the management of oral infections like periodontal disease by reducing the levels of reactive oxygen species. The current study was designed to evaluate the effectiveness of Blue M, an oxygenated mouthwash as an adjunct to scaling and root planing (SRP) in the treatment of chronic periodontitis (CP). Materials and Methods: Forty-two CP patients were randomly divided into 3 groups (Group A – only SRP, Group B – SRP with oxygenated blue®m mouthwash, and Group C-SRP with 0.2% chlorhexidine [CHX] mouthwash). Clinical parameters-plaque index, gingival index, probing pocket depth, and relative attachment level were evaluated at baseline, 1 month, and 3 months while microbial analysis was carried out, using chairside N-benzoyl-DL-arginine-2-naphthylamide Assay for detection of either presence or absence of Treponema denticola, Porphyromonas gingivalis, and/or Tannerella forsythia at baseline and 3 months. Results: All groups showed a significant reduction in clinical and microbiologic parameters from baseline to 3 months (P < 0.05). Intergroup analysis showed Group B and Group C to be significantly better than Group A (P < 0.05) while Group B showed similar results when compared to Group C (P > 0.05). Conclusion: Blue M mouthwash showed better improvement as compared to SRP alone while it showed similar improvements in clinical as well as microbiologic parameters when compared with CHX. It can be concluded that Blue M mouthwash could well be a futuristic prospect as an alternative to chemical agents like CHX in the treatment of CP.