{"entity":{"id":"immune-colitis","kind":"term","name":"Immune-mediated colitis and diarrhoea","aka":["colitis","immune colitis","immune-mediated colitis","checkpoint colitis","ipilimumab colitis","diarrhoea","diarrhea","grade 3 diarrhoea","severe diarrhoea","enterocolitis"],"tldr":"Inflammation of the bowel caused by immunotherapy releasing the immune system against the gut lining, producing diarrhoea that can be severe. It is the commonest serious side effect of CTLA-4 antibodies and is treated with steroids and, if needed, infliximab.","summary":"Colitis occurs in 10-15% of patients on ipilimumab (higher with nivolumab combination) and 1-3% on PD-1 antibodies alone, typically 6-8 weeks in; grade 3 diarrhoea (≥7 stools/day over baseline) requires holding treatment and high-dose steroids, with infliximab or vedolizumab for refractory cases, and perforation is the feared complication. Faecal microbiota transplantation has reversed refractory colitis in case series, and the gut microbiome influences both colitis risk and response. Chemotherapy and kinase inhibitors (irinotecan, capecitabine, neratinib, abemaciclib, EGFR inhibitors) cause diarrhoea by different mechanisms managed with loperamide and dose adjustment, and diarrhoea is a leading reason for stopping oral targeted drugs.","asOf":"2026-09-09","wikipedia":"https://en.wikipedia.org/wiki/Colitis","links":[{"label":"Wikipedia","url":"https://en.wikipedia.org/wiki/Colitis"},{"label":"Macmillan: pembrolizumab","url":"https://www.macmillan.org.uk/cancer-information-and-support/treatments-and-drugs/pembrolizumab"},{"label":"Schneider et al., ASCO guideline on immune-related adverse events (JCO 2021)","url":"https://doi.org/10.1200/JCO.21.01440"},{"label":"Macmillan: pembrolizumab (Keytruda)","url":"https://www.macmillan.org.uk/cancer-information-and-support/treatments-and-drugs/pembrolizumab"}],"tags":[],"related":["irae","immune-endocrinopathy","dose-modification"],"cancers":["tnbc","lung-cancer","nsclc","sclc"],"sections":["supportive-care","immunotherapy"],"technologies":["checkpoint-inhibitor","microbiome-modulation-io"],"targets":[],"drugs":["ipilimumab","irinotecan"],"companies":[],"institutions":[],"pathways":[],"terms":[],"trials":[],"people":[],"bottlenecks":[],"keyPapers":[],"journals":[],"dependsOn":[],"notes":["On pembrolizumab for triple-negative breast cancer, Macmillan says to contact the hospital straight away on the 24-hour number if you pass more stools than normal, pass stools at night, have watery or loose stools, or have uncomfortable tummy cramps or pain, during treatment or after it ends. Do not treat it at home as ordinary diarrhoea without ringing.","Lung cancer: Macmillan says to contact the hospital straight away on the 24-hour number during or after checkpoint treatment for passing more stools than is normal for you, passing stools at night, or a stoma that is more active than usual, and separately that if you have not been able to pass stools for over 2 days and are being sick, to contact the 24-hour number straight away."],"category":"Side effects"},"route":"/terms/immune-colitis/","neighbours":{"term":[{"id":"dose-modification","kind":"term","name":"Dose reduction, interruption and discontinuation","route":"/terms/dose-modification/"},{"id":"irae","kind":"term","name":"Immune-related adverse events (irAEs)","route":"/terms/irae/"},{"id":"immune-endocrinopathy","kind":"term","name":"Immune-related endocrinopathies (thyroiditis, hypophysitis)","route":"/terms/immune-endocrinopathy/"},{"id":"urgent-help-tnbc","kind":"term","name":"When to seek urgent help with triple-negative breast cancer (NHS 111 and 999)","route":"/terms/urgent-help-tnbc/"}],"cancer":[{"id":"lung-cancer","kind":"cancer","name":"Lung cancer (all types)","route":"/cancers/lung-cancer/"},{"id":"nsclc","kind":"cancer","name":"Non-small-cell lung cancer","route":"/cancers/nsclc/"},{"id":"sclc","kind":"cancer","name":"Small-cell lung cancer","route":"/cancers/sclc/"},{"id":"tnbc","kind":"cancer","name":"Triple-negative breast cancer (TNBC)","route":"/cancers/tnbc/"}],"section":[{"id":"immunotherapy","kind":"section","name":"Immunotherapy","route":"/fronts/immunotherapy/"},{"id":"supportive-care","kind":"section","name":"Supportive Care & Survivorship","route":"/fronts/supportive-care/"}],"technology":[{"id":"checkpoint-inhibitor","kind":"technology","name":"Immune checkpoint inhibitors","route":"/technologies/checkpoint-inhibitor/"},{"id":"microbiome-modulation-io","kind":"technology","name":"Microbiome modulation to unlock immunotherapy","route":"/technologies/microbiome-modulation-io/"}],"drug":[{"id":"ipilimumab","kind":"drug","name":"Ipilimumab","route":"/drugs/ipilimumab/"},{"id":"irinotecan","kind":"drug","name":"Irinotecan (and liposomal irinotecan)","route":"/drugs/irinotecan/"}]}}