The remarkably diverse effects of the catecholamines and similar sympathomimetic agents are directly related to an understanding of the classification and different types of adrenoreceptors. Characteristics and physiological regulatory mechanisms of the receptor result in variable response of organ systems to catecholamines stimulation. Different adrenoreceptors regulate distinct physiological processes by controlling the synthesis or release of a variety of second messengers. The goal of this review was to turn one's attention to the below mentioned aspects. There are three known subtypes of each alpha1-, alpha2- and beta-adrenoreceptor types. Structure of the adrenoreceptors, which belong to subtypes of the same receptor type, is similar and structure of the adrenoreceptors of the separate types is very different. Genetic peculiarities of the receptors may influence liability to some diseases. Acting on the adrenoreceptors may change function of many organs and may serve for the treatment of cardiovascular, respiratory tract diseases and allergic reactions. Selective acting on the adrenoreceptors of the separate subtypes may have the different effect on the organs. Great consideration is given for that property in the development of new drugs: substitution by different chemical radicals leads to increasing selectivity for the separate subtypes of the adrenoreceptors. The prolonged use of the adrenomimetics may lead to refractoriness.