Relevance. In clinical and expert practice, there are cases of the development of pathological processes for the administration of the local anesthetic lidocaine in the form of toxic reactions and anaphylaxis. The morphological signs revealed in this case are considered nonspecific. Description of expert observation. The case of the death of a child from intramuscular administration of ceftriaxone in 2% lidocaine solution is considered, which served as the basis for the commission of a forensic medical examination. Conclusion. Objectification of expert conclusions about the toxic effect or the development of anaphylactic shock on the intramuscular administration of ceftriaxone in 2% lidocaine solution due to the low specificity of manifestations, at the same time, it can be based on a detectable complex of pathomorphological changes in combination with the mandatory forensic chemical determination of the concentration of these agents in the internal organs and blood, assessment of the sequence of development of the clinical picture, taking into account the route of administration of drugs. The considered problem requires further in-depth study.