A Comprehensive Review of Natural Products Against Allergic Rhinitis and Asthma: From Sensitization to Chronic Remodeling

Allergic rhinitis (AR) and allergic asthma are chronic airway inflammatory diseases characterized by three phases: sensitization, acute exacerbation, and chronic remodeling. While conventional antiallergic drugs provide symptomatic relief, they often face limitations including drug resistance, side effects, and inability to reverse chronic airway remodeling. Natural products have emerged as promising therapeutic alternatives due to their multi-target effects and safety profiles. This review systematically summarizes natural small molecules targeting distinct pathological mechanisms across the three phases of AR and asthma, introducing a chronopharmacological perspective for stage-specific therapeutic strategies. During sensitization, flavonoids (quercetin, luteolin, apigenin, baicalin) and polyphenols (curcumin, resveratrol) target the epithelial-dendritic cell axis by suppressing alarmin release and blocking dendritic cell maturation. In acute exacerbation, flavonoids (hispidulin, quercetin) and isoquinoline alkaloids (coptisine) exhibit rapid intervention through mast cell stabilization and neurogenic inflammation suppression. In chronic remodeling, stilbenes (resveratrol) and flavones (baicalin, baicalein) reverse established structural changes through TGF-β1/Smad, PTEN/PI3K/AKT, and PDGF-BB/PDGFR-β pathways. Mapping natural compounds to specific disease stages provides a molecular basis for precision medicine approaches.