Retrospective epidemiological analysis of acute baclofen poisoning

Introduction. Acute baclofen poisoning occupies a significant place in the structure of acute poisoning of chemical etiology. The increase in the frequency of baclofen poisoning is associated with the expansion of its use in neurological practice. Clinical toxicology challenges include the difficulties in identifying and diagnosing of baclofen poisoning due to the frequent mimicry of neurological pathology, leading to delays in treatment. In order to improve approaches to the diagnosis and treatment of baclofen poisoning, an epidemiological analysis was conducted.

The purpose of the study was to carry out a retrospective analysis of acute baclofen poisoning in St. Petersburg from 2021 to 2024.

Material and methods. Electronic medical records and the results of chemical and toxicological studies of biomaterial from patients hospitalized at the Acute Poisoning Center of the I.I. Dzhanelidze St. Petersburg Research Institute of Emergency Medicine for the period from 2021 to 2024 were studied. The epidemiological analysis included a quantitative assessment of the incidence of acute baclofen poisoning among residents of St. Petersburg and was calculated for 100 thousand people.

Results. In the period from 2021 to 2024, there was an upward trend in the number of acute baclofen poisoning (y = 0.834x − 0.525; R² = 0.6839). In the dynamic series, the period of increase in baclofen poisoning prevailed over the period of decline. 23% of patients were hospitalized in the intensive care unit of the Acute Poisoning Center, 41.8% of them required artificial lung ventilation (ALV).

Limitations. The limitations of the study are related to the retrospective nature of the analysis and the possible underestimation of cases of mild poisoning that do not require hospitalization. Nevertheless, the identified trends confirm the need to include baclofen in drug safety monitoring programs and the development of specialized antidotes, baclofen antagonists, which are under experimental research.

Conclusion. As a result of the study, a significant epidemiological significance of acute baclofen poisoning for residents of St. Petersburg was revealed, which requires improvement of diagnostic and treatment methods for these poisonings, as well as tightening of control measures to prevent the spread of this drug among the population.

Compliance with ethical standards. The study was approved by the local Ethics Committee of the I.I. Dzhanelidze St. Petersburg Research Institute of Emergency Medicin (Protocol No. 4 dated May 22, 2025) conducted according to the European Convention for the Protection of Vertebrate Animals used for Experimental and other Scientific Purposes (ETS No. 123), European Union Directive 2010/63 EU of 22.09.2010 on the protection of animals used for scientific purposes.

Аuthor’s contribution:
Narzikulov R.A. – concept and design of the study, collecting and processing the material, text writing;
Batotsyrenov B.V. – concept and design of the study, editing;
Ikhaev Kh.S. – collecting and processing the material;
Medvedev A.A. – statistical data processing, text writing;
Lodyagin G.A. – text writing;
Merenkova E.N. – text writing.
All co-authors – final approval of the article, responsibility for the integrity of all parts of the article.

Conflict of interest. The authors declare no apparent and potential conflicts of interest in relation to the publication of this article.

Funding. The study had no sponsorship.

Received: June 23, 2025 / Revised: October 8, 2025 / Accepted: March 27, 2026 / Published: April 30, 2026

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