Aim of the study was structural and functional analysis of the body of laboratory rats on the background of administration of biogenic drugs which include micro- and macroelements and substances of animal and vegetable origin. We have analyzed intergroup difference of morphometric parameters of adrenal glands structures. We revealed particular micromorphological features of adrenal glands structures on the background of biological products administration in animals participating in the subacute experiment. Morphometric changes of the studied gland in rats treated with an aqueous solution of Calcefit-5 were noticed. Morphological changes in the structures of adrenal glands, particularly changes of the beam zone, were objective verification tools of rat’s response to experimental conditions.