Relevance In recent years, the negative role of some pharmaceuticals effect on the liver of an agricultural bird which hepatotoxicity sharply increases in theprocess of biotransformation in the connection with the formation of active metabolites was revealed. Poisoning with xenobiotics and hormone and protein metabolites accumulating in an organism causes intoxication and promotes increase in intensity of peroxide lipid oxidation. Therefore, biooxidantsuse which include fat-and water-soluble vitamins is necessary. Considering this, together with the staff of CJSC Petrokhim we developed a new complex drug which contained carotene, bioflavonoid complex of a larch, and fat-soluble vitamins. The drug was called Karoflavin. The purpose of the work was to study the possible use of karoflavin inbroilers with hepatosis. Results of the study The obtained resultsshowed highgrowth stimulating activity and biological availability of karoflavin, and its hepatoprotective properties. After karoflavin use bird average daily bodyweight increased by 9.5 and 10.3%, while forage use decreased by 1.1 and 1.6%, calcium serum blood level increased by 35.0 and 35.9%, vitamin A increased by 20.3 and 25.6%, aspartateaminotransferase activity decreased by 20.3 and 21ю1%, alanineaminotransferases-by 20.3 and 22.9%, glucose level decreased by 26.1 and 25.6%.