#37 Understanding IBS in IBD - with Professor Peter Irving

Send us Fan MailIn our latest episode of Wrestling the Octopus: the IBD Patient Podcast, Nigel and I chat with Professor Peter Irving, IBD consultant at Guy’s & St Thomas’ Hospital in London, about the confusing but incredibly common overlap between irritable bowel syndrome (IBS) and inflammatory bowel disease (IBD).We were keen to record this episode as many IBD patients have an IBS overlap - and it can be devilishly hard to know if you're having an IBD flare or if it's IBS. Professor Irving shares some great tips on this.What IBS Really IsProfessor Irving tells us that IBS is “a disorder of the interaction between the gut and the brain” and requires abdominal pain plus changes in stool form or frequency. It’s now classed as a disorder of gut–brain interaction, not a “functional” problem - a term that often leaves patients feeling dismissed.Why IBS Is More Common in IBDAbout 30–40% of people with Crohn's disease or ulcerative colitis experience IBS‑type symptoms. Reasons include:🔥 Post‑inflammatory sensitivity - like post‑herpetic neuralgia after shingles🌀 Altered motility🧫 Microbiome changes🧠 Psychological stress, which affects gut–brain signallingIBS vs an IBD Flare - How to TellIt’s tricky. Some clues point more toward active IBD:🌙 Nocturnal symptoms🩸 Rectal bleeding⚖️ Weight lossOften though, objective tests are needed:🧪 Calprotectin🖥️ Ultrasound or imaging📹 EndoscopyBile Acid Malabsorption - A Common MimicEspecially in Crohn’s disease affecting the terminal ileum.Testing options include:☢️ SeHCAT scan 💊 Trial of bile acid sequestrantsManaging IBS Symptoms in IBDTreatment depends on symptoms and patient preference:🌿 Antispasmodics (mebeverine, Buscopan)🍃 Peppermint oil (Colpermin)🧉 Ginger🚽 Carefully-supervised loperamide💊 Low‑dose tricyclic antidepressants for pain modulation🧘 Stress‑management and lifestyle support🥗 Dietetic input, which can be transformativeThe Low FODMAP DietProfessor Irving helped bring the low FODMAP diet from Australia to the UK.It reduces fermentable carbohydrates that trigger gas, bloating, and diarrhoea, and can be useful in helping IBD patients to manage their IBS.It’s not meant to be long‑term - it’s a structured tool that helps patients regain control over gut health.A Final ThoughtIBS in the context of IBD is real, common and complex. With the right tests, the right conversations, and the right tools - from diet to medication to lifestyle - patients can feel heard, supported and empowered.Professor Irving also has an IBD podcast of his own - called Digesting - alongside a set of international IBD experts at the BRIDGe Group. Listen here.Follow Rachel at @bottomlineibdFollow Nigel at @crohnoid