Chronic carbon monoxide (CO) exposure remains an underrecognized cause of long-term hypoxic injury to the gastrointestinal tract, while esophageal morphological alterations and potential phytotherapeutic correction are insufficiently explored. To investigate structural and morphometric alterations of the esophagus induced by chronic CO exposure and to evaluate the corrective efficacy of Silybum marianum and Carthamus tinctorius extracts. An experimental study was conducted on 250 white outbred rats aged 3 and 9 months. Chronic CO exposure was modeled at 200–300 mg/m³. Animals were assigned to five groups: control, CO exposure, CO + Silybum marianum, CO + Carthamus tinctorius, and CO + combined phytocorrection. Histological, morphometric, and immunohistochemical analyses were performed, followed by statistical evaluation. Chronic CO exposure induced marked epithelial atrophy, interstitial edema, microcirculatory disturbances, and inflammatory infiltration of the esophageal wall, with more pronounced changes in older animals. Phytocorrection significantly attenuated inflammatory and dystrophic alterations and promoted tissue regeneration. Silybum marianum demonstrated superior anti-inflammatory and regenerative effects compared to Carthamus tinctorius, particularly in younger animals. Chronic CO exposure causes persistent hypoxia-driven esophageal injury. Phytocorrection, especially with Silybum marianum, effectively restores esophageal morphology and mitigates inflammation, highlighting its potential as a therapeutic strategy for hypoxia-induced esophageal damage. 

Carbon monoxide, Chronic hypoxia, Esophageal injury, Experimental toxicolo

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