The Safety of Low Concentration Hypochlorous Acid as an Oral Gargle Solution and Its Anti-Microbial Effects

Abstract

Received March 15, 2011 Revised May 19, 2011 Accepted May 19, 2011 Address for correspondence Tae Young Jang, MD, PhD Department of OtorhinolaryngologyHead and Neck Surgery, Inha University College of Medicine, 7-206 Sinheung-dong 3-ga, Jung-gu, Incheon 400-711, Korea Tel +82-32-890-3471 Fax +82-32-890-3580 E-mail jangty@inha.ac.kr Background and ObjectivesZZThe authors aimed to evaluate the safety of low concentration hypochlorous acid as an oral gargle solution. To do this, we carried out in vitro and in vivo experiments and evaluated its efficacy by compared with normal saline and chlorhexidine gargle using throat culture before and after gargling. Materials and MethodZZThe authors treated oral mucosal epithelial cell with 3.5 ppm hypochlorous acid and evaluated cytotoxicity. For evaluation of morphological change, oral mucosa specimens were obtained during surgery before 30 minutes and 2 hours after treatment with hypochlorous acid. The specimens were evaluated with light microscopy. For evaluation of efficacy, we performed oral gargle with normal saline, chlorhexidine and hypochlorous acid in 10 healthy volunteers. The throat cultures were performed before and after each gargling. Staphylococcus aureus, Streptococcus pneumoniae, Streptococcus pyogenes, Haemophilus influenzae, Klebsiella pneumoniae, Aspergillus fumigatus, Rhizopus oryzae were evaluated semi-quantitatively (Grade 0 to 4). ResultsZZThere was no cellular toxicity in MTT assay and the morphological changes were not observed. Both chlorhexidine and hypochlorous acid showed significant decrease of microbes (chlorhexidine: p=0.036, hypochlorous acid: p=0.031). There was no significant differences between them (p=0.217). ConclusionZZLow concentration hypochlorous acid is safe for the oral mucosal epithelium and has antimicrobial efficacy similar to that of chlorhexidine. Korean J Otorhinolaryngol-Head Neck Surg 2011;54:403-7