Irritable bowel syndrome (IBS) is a disorder of gut–brain interaction (DGBI) with high prevalence and a significant impact on quality of life. Its frequent overlap with other DGBI such as functional dyspepsia, functional constipation and gastroesophageal reflux disease, as well as with extra-digestive comorbidity including fibromyalgia, chronic fatigue syndrome and endometriosis, represents a relevant clinical challenge. This coexistence is associated with a higher symptom burden, poorer prognosis, fluctuating clinical course, and lower response to conventional treatment. DGBIs share pathophysiological mechanisms such as visceral hypersensitivity, dysmotility, intestinal dysbiosis, dysfunction of the gut–brain axis, and neuroinflammation, which explain their frequent overlap. Evaluation must be comprehensive, taking into account symptoms across different anatomical regions, psychological comorbidities, and the dynamic evolution of subtypes, always prioritizing the most disabling symptom. Treatment should be guided by the predominant symptom axis and combine pharmacologic strategies such as neuromodulators with psychosocial interventions, cognitive behavioral therapy, and lifestyle-based approaches. Overlaps with gynecological and systemic conditions such as interstitial cystitis or bladder pain syndrome and endometriosis require a multidisciplinary approach. Recognizing and addressing IBS overlap with other disorders helps avoid fragmented treatment, improves quality of life, and reduces unnecessary use of healthcare resources. This patient-centered approach, grounded in shared mechanisms, is essential for effective, empathetic, and evidence-based care.
Keywords: Irritable bowel syndrome. Visceral hypersensitivity. Comorbidity. Gut-brain axis. Quality of life.
