Studies support chlorine dioxide mouthwash use for bad breath, but it appears the mouthrinse that is activated upon use, like Profresh, is more effective than the other versions with stabilized chlorine dioxide (OxyFresh, Closys, Therabreath). If you’ve not had good results with those, it’s worth giving this a try. But remember – brushing, flossing, and tongue scraping are the best way to shift the balance of your oral bacteria toward health and that alone will improve bad breath if bacterial in nature.