NAZA - Nottingham/Astra ZenecA Prospective IBD Cohort Study

This is an observational study — meaning researchers are not testing a new treatment, but collecting detailed health data — from people with Crohn's disease or ulcerative colitis (together called IBD). The goal is to better understand why these conditions flare up and how they respond to treatment over time, by tracking blood, stool, and tissue samples alongside standard care. **You may be eligible if...** - You are at least 16 years old - You have active Crohn's disease (with elevated inflammation markers or visible ulcers on colonoscopy) OR active ulcerative colitis affecting a significant part of your colon - You are about to start or change a treatment for IBD - You are willing to provide blood, stool, and possibly tissue samples over time **You may NOT be eligible if...** - You are under 16 years old - You do not have a confirmed diagnosis of Crohn's disease or ulcerative colitis - You are unable or unwilling to provide consent or follow the study schedule Talk to your doctor to see if this trial is right for you.