Pharmacokinetics and Pharmacodynamics of Phenibut with Their Potential Dependence on Endogenous Hydrogen Sulfide: A Literature Review

Aims: The aim of the study was to analyze the current literature data on the pharmacokinetics and pharmacodynamics of phenibut, as well as to evaluate their potential dependence on endogenous hydrogen sulfide.

Materials and Methods: Retrospective analysis of literature data was carried out on the basis of data from Scopus, Web of science, PubMed, ScienceDirect, UpToDate databases, as well as using the Google search service. When searching for information on the investigated problem, various combinations of keywords in Ukrainian and English were used: “phenibut”, “pharmacokinetics”, “pharmacodynamics”, “pharmacology”, “hydrogen sulfide”, “H2S”, “mechanism of action”, “physiology”, “pathophysiology”. During the processing the search results, either the most recent publications (for the last 10 years) or the latest publications on this issue (regardless of the age) were selected. After studying the data of the search results, 38 scientific sources were selected that met the terms of the request.

Results: Despite its promising profile, phenibut is not without certain limitations and problems. Its effectiveness in the treatment of anxiety disorders is considered moderate compared to traditional anxiolytics such as benzodiazepines. In addition, due to the limited number of studies, its safety and potential side effects with long-term use require further study. Overall, phenibut is an interesting and promising drug that deserves further investigation, but limitations of its use may be related to individual characteristics of pharmacokinetics and pharmacodynamics. In our opinion, the cause of such individual characteristics may be certain endogenous factors that vary among different people. One of these endogenous modulators includes hydrogen sulfide, which regulates a wide range of biochemical and physiological processes.

Conclusion: The broad and diverse influence of endogenous hydrogen sulfide on the course of biochemical and physiological processes in the body prompts the study of its potential modulating influence on the pharmacological properties of drugs. A preclinical study of the pharmacokinetics and pharmacodynamics of drugs (in particular, phenibut) taking into account the level of hydrogen sulfide in the body will allow further optimization of therapeutic schemes by adjusting the background level of this transmitter.