Phytochemicals in Asthma Management: Mechanism, Translational Gap and Clinical Integration

ABSTRACT Asthma is a chronic inflammatory airway disease characterized by oxidative stress, immune dysregulation, and airway remodeling. Conventional therapies such as corticosteroids and bronchodilators provide symptomatic relief but are limited by adverse effects and incomplete efficacy in heterogeneous phenotypes. Phytochemicals, including flavonoids, alkaloids, terpenoids, saponins, and coumarins, have emerged as promising adjuncts due to their molecular mechanisms targeting key inflammatory pathways. A systematic review was conducted following PRISMA guidelines across PubMed, Scopus, and Web of Science (2004–2026). Studies reporting asthma‐related outcomes of phytochemicals in preclinical or clinical settings were included. Evidence quality was assessed using the GRADE framework to distinguish randomized controlled trials (RCTs) from observational and preclinical studies. Quercetin modulates PI3K/Akt/mTOR signaling and suppresses Th2 cytokines, reducing airway inflammation. Glycyrrhizin inhibits NF‐κB activation and enhances corticosteroid responsiveness, with derivatives such as SHR‐1905 currently in Phase III trials for severe asthma. Piperine, a bioenhancer, is under evaluation in inhalable formulations. Other phytochemicals, including saponins from Bacopa monnieri and coumarins from Amburana cearensis , remain at preclinical stages but demonstrate immunomodulatory and bronchodilatory potential. Despite these advances, translational gaps persist. Clinical adoption is hindered by poor bioavailability, limited randomized controlled trials, and safety concerns such as hepatotoxicity with glycyrrhizin. Integrating phytochemicals into current therapeutics offers a pathway toward personalized, safer, and more effective asthma management. This review synthesizes molecular mechanisms, highlights translational gaps, and proposes strategies for clinical integration, bridging bench discoveries to bedside applications of phytochemicals in asthma management.