NanoPhyto formulations: A promising approach for targeted therapy of gastrointestinal infections, clinical advancements, and future perspectives.

GI infections caused by bacterial pathogens-including H. pylori, C. diff, Salmonella, and E. coli-represent a major global health burden, exacerbated by rising antimicrobial resistance and the limited bioavailability of conventional therapeutics. Phytochemicals such as polyphenols, terpenoids, and alkaloids offer promising antimicrobial, anti-inflammatory, and mucosal-protective activities but suffer from poor solubility, chemical instability, and inadequate site-specific delivery in the harsh GI environment. Nanocarrier-based delivery systems-including polymeric, lipid-based, and hybrid platforms-have emerged as a rational strategy to overcome these limitations by enhancing phytochemical stability, enabling mucus adhesion or penetration, and facilitating stimuli-responsive release at infected or inflamed sites. This review critically examines how nanocarrier design-guided by phytochemical chemistry and GI biological barriers-determines therapeutic outcomes in preclinical models of H. pylori infection, gastric ulcer, and inflammation-associated carcinogenesis. We highlight recent advances in pH-, enzyme-, and ROS-responsive carriers, AI-driven formulation optimization, and key translational challenges including long-term toxicity, regulatory pathways, and clinical readiness. By focusing exclusively on infection-relevant NanoPhyto formulations, this review provides a structured framework for the rational development of clinically viable nanotherapeutics for GI infections.