The use of medicinal products (MP) with contraventions of officially approved instructions regulations (off-label), especially in pediatrics, is an actual problem of health care. This article studies MP off-label use structure in children and role of such drugs use in development of serious adverse reactions (AR), on the basis of Russian spontaneous reports database analysis. The results confirm that off -label MP prescription is an independent factor for AR developing risk. The study proved that spontaneous reports method is effective in studying of medicines use security problems and allows to develop recommendations that can significantly reduce the risk of pharmacotherapy complications, including in pediatric patients. © 2016, Pediatria Ltd. All rights reserved.