A patient with gingivitis was prescribed a gargle with a certain preparation. Its antiseptic properties are determined by atomic oxygene that slivers in presence of organic substances. It has also deodorant, adstringent (anti-inflammatory), and in big concentrations - cauterizing effect. Water solutions are used for bathing of wounds, mouth gargling and in higher concentrations - for burn treatment. It is also used for gastric lavage in case of poisoning. Name this preparation: