Antibiotic Therapy in Dyssynergic Defecation With Microbial Overgrowth

Key Points Dyssynergic defecation is frequently accompanied by small intestinal microbial overgrowth, often with methane predominance, making the role of antibiotics a relevant clinical question. In tertiary practice, dyssynergic defecation patients with SIBO/IMO show heterogeneous responses to rifaximin or metronidazole: some report global improvement in bloating and constipation, whereas others experience worsening stool consistency and more difficult evacuation. These contrasting experiences highlight the need for prospective, phenotype‐based studies to clarify when adjunctive antibiotic therapy is beneficial, neutral, or potentially harmful in dyssynergic defecation with microbial overgrowth.