Hydrogen Peroxide Mouthwash is an antiseptic that treats gum diseases and helps remove stains on teeth. It does so by releasing oxygen and causing effervescence which kills bacteria. In addition, it breaks apart the chemical bonds that create yellow-brown stains on teeth, resulting in a whitening effect. Gingivitis, Periodontol disease, anaerobic infections, peri-implantitis, mouth ulcers, during orthodontic treatment, after minor surgery.