Pharmacological Mechanisms of Anxiolytic Phytotherapeutics and Their Action on the GABA System

Abstract

Anxiety is one of the most prevalent mental disorders today and is associated with an imbalance between excitatory and inhibitory neurotransmitters in the central nervous system, especially gamma-aminobutyric acid (GABA). In this context, anxiolytic herbal medicines have gained attention as therapeutic alternatives to benzodiazepines due to their lower potential for dependence and fewer adverse effects. This study aimed to analyze the pharmacological mechanisms of anxiolytic herbal medicines, focusing on their action on the GABAergic system and their effects on anxiety modulation. This is an integrative literature review with a qualitative and descriptive approach, based on studies published between 2019 and 2025 in the SciELO, LILACS, PubMed, and Web of Science databases. The results demonstrated that herbal medicines such as Passiflora incarnata, Valeriana officinalis, and Melissa officinalis contain bioactive compounds capable of modulating GABA-A receptors, increasing GABA availability, and reducing neuronal excitability. Although benzodiazepines remain more effective in acute anxiety disorders, herbal medicines showed a more favorable safety profile and promising results in mild and moderate anxiety cases. However, limitations related to extract standardization, the scarcity of robust clinical trials, and methodological differences among studies were identified. It is concluded that anxiolytic herbal medicines present relevant therapeutic potential, although further clinical studies are required to confirm their efficacy and safety.