Despite the studies conducted in the field of biochemical changes in chronic tonsillitis, some issues of the functional state of lipids and antioxidant system are still not fully disclosed. Damaging character of action of LPO activation, presence of great number of factors of such activation at some ENT-proofs necessitate investigation of AOS-APK state at chronic tonsillitis, in pre- and postoperative periods and finding the ways for correction of revealed disturbances in LPO-APK system in the focus of inflammation at chronic tonsillitis. In this connection, it is an urgent task to identify disorders of reactive oxygen species generation and the state of anti-peroxide-antiradical system protection in the tissues of palatine tonsils and blood in patients with HT, as well as to find methods of their correction. The monograph aims to study the work of generation of reactive oxygen species and the state of antioxidant system, phospholipid metabolism in the tissue of the palatine tonsils and blood in toxic-allergic form of chronic tonsillitis of 1st and 2nd degree.