The Cost of the Cure: Antibiotic Exposure as a Risk Factor for Irritable Bowel Syndrome

The intricate interplay between the gut microbiome and the enteric nervous system remains a paramount focus in understanding the multifactorial pathogenesis of disorders of gut-brain interaction (DGBI), most notably irritable bowel syndrome (IBS). While the clinical entity of post-infectious IBS is well-established, the independent, long-term pathophysiological impact of iatrogenic antibiotic exposure is garnering critical attention within neurogastroenterology. This narrative review provides a comprehensive synthesis of current epidemiological and mechanistic evidence positioning antibiotic-induced microbial depletion as a potential predisposing factor for incident IBS. By evaluating recent literature, we highlight epidemiological trends demonstrating a consistent, dose-dependent relationship between cumulative antibiotic courses, particularly broad-spectrum agents, and an elevated risk of developing IBS, independent of prior acute enteric infections. Furthermore, we explore the mechanistic underpinnings of this association, focusing on how systemic antibiotics induce persistent, detrimental alterations in commensal diversity. This resulting dysbiosis initiates a proposed cascade of downstream consequences, including compromised epithelial barrier integrity, persistent low-grade mucosal inflammation, and altered bile acid metabolism. These localized disruptions serve as established triggers for visceral hypersensitivity and dysregulated gastrointestinal motility communicated via the gut-brain axis. Ultimately, this review underscores that antibiotic exposure may act as a significant, modifiable risk factor for IBS pathogenesis. Recognizing this substantial iatrogenic risk reinforces an urgent clinical imperative for stringent antimicrobial stewardship and emphasizes the necessity for future research directed toward prophylactic, microbiome-sparing strategies to mitigate the escalating global burden of DGBIs.