Despite the enormous successes that have been achieved in the fight against infectious diseases thanks to mass preventive vaccination, primarily the reduction of child mortality, оutbreaks of vaccine-preventable diseases sometimes occur. One of the reasons is unjustified medical exemptions from vaccinations, which were widely used in the past, the shortcomings of taking into account adverse events after immunization as well as parental refusals (complete or partial) from preventive vaccinations. The article presents data from a retrospective analysis of medical records of patients sent for consultation with an allergist-immunologist to decide on the possibility of vaccination against the new coronavirus infection (COVID-19), including to confirm previously issued medical exemptions. The study included 87 patients (39 men and 48 women), most of them were of working age. Sixty-eight patients (78.2%) had previously received medical exemptions from vaccination, including 14 (20.6%) based on information about adverse events after immunization, and 32 (47.1%) based on adverse reactions for the administration of other medications, and in 22 (32.3%) only on the basis of a diagnosis of any allergic disease. At the same time, medical documentation confirming the facts of adverse events after immunization or adverse reactions to medications was absent in the vast majority of cases. In addition, 3 patients were not vaccinated in childhood due to parental refusal, and another 16 patients were contacted to assess the potential risk of developing side effects after vaccination due to the presence of allergic diseases (bronchial asthma, allergic rhinitis, atopic dermatitis, chronic urticaria, recurrent angioedema). Based on clinical and anamnestic data and, if necessary, laboratory and instrumental studies, temporary contraindications for vaccination were identified in only 6 (27.2%) patients. There were no absolute contraindications. In other cases, stable remission was observed or the disease was fully or partially controlled with medication, which was not a contraindication for vaccination at the time of treatment. Thus, in most cases, medical exemptions from vaccinations are unfounded or become irrelevant over time. At the same time, the lack of medical documentation seriously makes it difficult to objectively assess the risk of developing adverse events after immunization in patients with allergic diseases.