What is irritable bowel syndrome, and what are its comorbidities?
Irritable bowel syndrome (IBS) is a chronic functional bowel disorder—with no identifiable organic lesion—that affects 10–15% of adults. It often presents with extragastrointestinal comorbidities that exacerbate the clinical picture and guide comprehensive management. For the complete diagnostic protocol and treatments, see our Irritable Bowel Syndrome page. Explore our targeted supplements in the Irritable Bowel Syndrome line.
- Fibromyalgia: coexists with IBS in 30–65% of cases—chronic widespread pain + fatigue + sleep disturbances—same mechanism of central hypersensitivity (central sensitization)—similar treatment (CBT, progressive exercise)
- Chronic Fatigue Syndrome (CFS): debilitating fatigue not relieved by rest + IBS in 50–80% of cases — pathophysiological link via the brain-gut axis and neuroinflammation
- Anxiety and depressive disorders: 50% of severe IBS cases — generalized anxiety disorder, panic disorder, depression — the brain-gut axis is bidirectional — treating anxiety directly improves IBS
- IBS and IBD (Crohn’s disease, ulcerative colitis): IBS can coexist with IBD in remission — functional symptoms persist even when inflammation is controlled — distinguish using fecal calprotectin and inflammatory markers
- Genetic component: risk increases 2–3-fold if a first-degree relative is affected—genes involved: serotonin transport, intestinal motility, mucosal permeability—environment and lifestyle remain key factors
Symptoms, Diagnosis, and Clinical Forms
- Associated gastrointestinal symptoms: nausea, dyspepsia, reflux (overlap syndrome)—30–40% of IBS cases also involve functional dyspepsia—treatments are often combined
- Post-infectious IBS: onset following acute gastroenteritis (Salmonella, Campylobacter, norovirus) — long-term alteration of the microbiota + intestinal permeability — see our page on intestinal disorders
- Rome IV criteria (diagnosis): recurrent abdominal pain ≥ 1 day/week for > 3 months associated with defecation or a change in bowel habits — diagnosis by exclusion (complete blood count + CRP + fecal calprotectin + anti-transglutaminase)
- Colonoscopy if: > 50 years old, blood in the stool, weight loss, fever, nighttime pain — always rule out colorectal cancer and IBD before confirming IBS
- Mucus in the stool: common in IBS (mucus without blood = functional) — blood in the stool = always organic → urgent diagnosis
Multifactorial treatments and a holistic approach
- FODMAP diet: first-line dietary intervention — 75% response rate — under dietary supervision — 3 phases (elimination, reintroduction, personalization) — identify individual triggers
- Targeted probiotics: Bifidobacterium infantis 35624 (pain + bloating + bowel movements) — Lactobacillus plantarum (bloating + flatulence) — see our probiotics page
- Antispasmodics: phloroglucinol (Spasfon, spasms) — mebeverine (for IBS) — enteric-coated peppermint (colon) — see our page on digestive spasms
- Low-dose antidepressants (amitriptyline, SSRIs): address visceral hypersensitivity and anxiety-depression comorbidities — take 4–6 weeks before effects are noticed — by prescription only
- CBT + gut-directed hypnotherapy + cardiac coherence: treatment of psychological comorbidities + direct reduction of IBS symptoms — high level of evidence
Lifestyle, genetics, and prevention of relapses
- Regular physical activity: 30 min × 5 times/week — improves motor function + gut microbiota + visceral hypersensitivity — adapted yoga (gentle poses; avoid intense exercise that worsens IBS-D)
- Hydration and meal schedule: 1.5–2 L/day of plain water — 3 meals at set times — do not skip meals — light snack if hungry between meals — eat in 20–30 min in a calm environment
- Preventing relapses: Maintain dietary habits (personalized FODMAPs) + daily cardiac coherence + physical activity + regular sleep (7–9 hours)
- Genetic counseling: Inform children of parents with IBS about an increased risk—early monitoring of symptoms—early lifestyle intervention (stress, diet)
- Medical follow-up: annual gastroenterology consultation — repeat evaluation if symptoms change — never self-diagnose IBS without ruling out organic causes — see our Irritable Bowel Syndrome page
