Buyang Huanwu decoction in the treatment of stroke: A review

• Systematic and Stage-Specific Review: For the first time, clinical evidence is organised systematically according to disease stage (acute, recovery and sequelae), clarifying the distinct therapeutic focus of each phase and providing clear theoretical guidance for stage-specific precision medication. • A modern scientific interpretation of the 'qi-tonifying and blood-activating' theory innovatively links the pathogenesis of 'qi deficiency and blood stasis' to the modern medical concept of 'neuro-immune-metabolic network dysfunction'. This is explained through the lens of energy metabolism (mitochondrial function) and fibrosis (platelet microvesicles), offering contemporary biological insights into classical TCM theory. • A comprehensive revelation of the synergistic mechanisms involving multiple components, targets and pathways. Table 1 provides a detailed overview of each herb's primary active constituents, molecular targets, signalling pathways and specific functions within the formula. This fully maps a modern pharmacological network diagram, demonstrating how BHD achieves synergistic effects through its 'sovereign, minister, assistant and messenger' herb combinations. • Highlighting cutting-edge mechanisms such as the gut-brain axis: It explains how BHD indirectly exerts neuroprotective effects by regulating the gut microbiota-immune-metabolic network, thereby embodying the integration of the holistic perspective of traditional Chinese medicine with modern systems biology. • Integrating clinical and basic research evidence: The manuscript incorporates clinical data, including randomised controlled trials and meta-analyses, as well as mechanistic studies from cellular and animal experiments, to substantiate the efficacy and safety of BHD. It demonstrates therapeutic value for special populations, such as the elderly and diabetic patients, offering lipid metabolism regulation and relapse prevention. Buyang Huanwu Decoction (BHD) is a traditional Chinese medicine (TCM) formula created by Wang Qingren during the Qing dynasty. It is renowned for its effects of Tonify qi, 1 1 A treatment method to tonify healthy qi. It is indicated for conditions due to qi deficiency. Circulate blood, and Unblock meridians 2 2 A treatment method to circulate blood, and unblock meridians. and is widely used in the treatment of stroke, for conditions such as hemiplegia and facial paralysis. The formula comprises seven herbs (see Table 2 for the complete list), including Astragalus membranaceus (Fisch.) Bunge, Angelica sinensis (Oliv.) Diels and Paeonia lactiflora Pall. This paper aims to provide a systematic review of the research progress on BHD for stroke treatment from 2019 to December 2025, covering both clinical efficacy and the multidimensional mechanisms of action. The review seeks to address the shortcomings of previous reviews regarding the comprehensive of mechanisms and their timeliness, while providing references for the modernisation of TCM. In order to evaluate the therapeutic effects of BHD on stroke comprehensively, we retrieved relevant literature published between 2019 and December 2025 from Chinese and English databases, including CNKI, Wanfang Database, PubMed and Web of Science. Search keywords included “Buyang Huanwu Decoction”, “stroke”, “mechanism”, “neuroinflammation”, “gut-brain axis” and the herbs that make up the decoction. This review was compiled by synthesising findings from animal experiments and clinical studies. Preliminary, low-certainty evidence from the 19 included RCTs suggests that BHD, when combined with Western medicine or acupuncture, may be associated with potential improvements in certain clinical outcomes such as National Institutes of Health Stroke Scale (NIHSS) and Barthel Index(BL) scores; however, these findings are derived from studies with methodological limitations and require validation in more robust trials. Its mechanism of action is complex, characterized by multi-component, multi-target, and multi-pathway effects. More specifically, this formula regulates cerebral blood circulation, protects neurons, promotes regeneration and stabilises the blood-brain barrier (BBB). It also modulates the gut-brain axis. This review summarises the available evidence on the efficacy and pharmacological mechanisms of BHD at different stages of stroke. While the findings may inform targeted clinical applications, further validation is required. However, current research is largely confined to animal or cellular experiments and lacks direct evidence from human studies. There are ongoing challenges in clinical practice, including dosage optimisation and herb-drug interactions. Future studies may overcome these limitations by leveraging systems biology and metabolomics, and through deeper exploration of gut-brain axis mechanisms. Concurrently, the development of novel formulations, such as nanocarriers, holds promise for enhancing bioavailability and efficacy, thereby maximizing its therapeutic potential. 3 3 Characterized by stabbing or migratory pain in a fixed location. Movable masses may be present. The tongue is purple or with ecchymosis. The pulse is wiry and hesitant. Often occurs when qi stagnation affects the flow of blood.