Oak extract contains triterpenoids, saponins, mono-, sesqui- and diterpenoids, phytosterols, flavonoids up to 1.2% L. (including catechines, leucoanthocyanidins, proanthocyanidins, coumarins, lignans, cyclotols, carbohydrates, multi-core aromatic compounds, as well as nitrogen-containing phenols, phenol glycosides and acids, their esters, aromatic and aliphatic hydrocarbons, alcohols, esters, aldehydes, ketones, higher fatty and cyclohexane carboxylic acids of the established structure. Tannin substances are extracted up to 40% from galls, fat oil – up to 10.8%, essential oil. Polyestolides, vitamins B, B2, B6, C, E, K, H, PP, pantothenic acid are found. It is used as an astringent and anti-inflammatory agent in cases of diseases of the oral cavity: gingivitis, stomatitis, amphodontosis instead of imported rhatany. It is also recommended for glottitis and pharyngitis. Good results are also marked in the treatment of burns.