Aim: To find out the specifics of the interpretation of non-performance or improper performance by medical or pharmaceutical employees of their professional duties, taking into account the practice of the ECHR. Materials and Methods: This article is based on the analysis of the international legal acts, the practice of the ECHR, national judicial practice, court statistics, criminal and medical law legal doctrine, official statistics of the Office of the Prosecutor General of Ukraine, analytical data based on the results of cooperation with the "Main Bureau of Forensic Medical Examination of the Ministry of Health of Ukraine". Dialectical, comparative, analytical, synthetic and system analysis research, hermeneutic methods were used. Results: In each specific case it is necessary to establish whether there is non-performance or improper performance of professional duties by medical or pharmaceutical employees, the result of which is the failure to fulfil his direct professional duties, provided for by regulatory and legal acts, job instructions, qualification requirements and standards of treatment. The patient's right to health care is not ensured by the guarantees provided for by national legislation, so patients file complaints with the ECHR. Conclusions: A single approach to the interpretation of such terms as "non-performance or improper performance by a medical or pharmaceutical employee his professional duties" is a guarantee of the uniformity of their enforcement and the formation of stable judicial practice in this category of criminal cases.