Basing on numerous literature data and own clinical observations a comprehensive analysis of the problem of gestational drug safety in the pharmacotherapy of pregnant women suffering from allergic diseases is given. This pathology affects the quality of life of the mother negatively but it is most importantly that it can have an adverse effect on the developing fetus in cases of the complicated pregnancy course. From the standpoint of the clinical pharmacology, the aspects of the optimal drug support for allergic diseases during pregnancy are considered taking into account the latest data on the complex system «mother — placenta — fetus — amniotic fluid» functioning. The information presented is of great practical importance for practicing physicians.