Traditional Chinese Medicine for Allergic Rhinitis: Mechanisms, Evidence, and Gut-Immune Axis Targets.

OBJECTIVE: Allergic rhinitis (AR) is a highly prevalent allergic disorder with increasing global incidence, and gut microbiota dysbiosis has emerged as a key pathogenic factor. This review systematically synthesizes evidence on how traditional Chinese medicine (TCM)-including single herbs, herbal formulas, and auxiliary therapies-alleviates AR by targeting gut microbiota, aiming to clarify mechanistic pathways and provide evidence-based support for clinical practice. METHODS: A comprehensive literature search was conducted in PubMed, China National Knowledge Infrastructure (CNKI), and Embase databases. Keywords included ["Traditional Chinese Medicine" or "TCM" or "Chinese herbal medicine" or "herbal formula"], ["allergic rhinitis" or "AR"], ["gut microbiota" or "intestinal microbiota"], ["immune regulation"], ["intestinal barrier"], and ["inflammatory mediator"]. Only peer-reviewed studies (human or animal models) focusing on TCM-gut microbiota-AR interactions were included; non-relevant, non-peer-reviewed, or duplicate articles were excluded. RESULTS: A total of 210 relevant studies were initially identified from the three databases (PubMed: 67, Embase: 55, CNKI: 88); subsequently, 122 duplicate records, 44 irrelevant records (38 with title mismatch, 6 including meetings, case reports, and protocols), and 22 low-quality studies were excluded, and finally 24 studies were included in this review. TCM exerts anti-AR effects through multi-targeted modulation of the gut microbiota-intestinal barrier-immune axis. TCM (eg, Astragalus membranaceus, Xiaoqinglong Decoction) increases the abundance of beneficial bacteria (eg, Lactobacillus, Bifidobacterium) and reduces pathogenic taxa, while promoting the production of microbial metabolites like short-chain fatty acids (SCFAs). TCM components upregulate tight junction proteins (ZO-1, Occludin) and activate the PI3K/Akt pathway to enhance intestinal epithelial integrity, reducing barrier permeability. TCM balances Th1/Th2/Treg cell subsets, inhibits NLRP3 inflammasome-mediated pyroptosis, and reduces pro-inflammatory mediators (IL-4, IL-5, TNF-α) while elevating anti-inflammatory cytokines (IL-10, IFN-γ). Clinical trials confirm TCM alleviates AR symptoms (nasal congestion, rhinorrhea), lowers serum IgE levels, and reduces disease recurrence. CONCLUSION: TCM ameliorates AR by integrating gut microbiota modulation, intestinal barrier repair, and immune regulation-highlighting its multi-pathway, multi-target advantages. Current limitations include insufficient large-scale randomized controlled trials and unclear TCM-microbiota crosstalk at the molecular level. Future research should leverage multi-omics technologies to decipher precise mechanisms and explore TCM-Western medicine combinations for optimized AR management.