Irritable Bowel Syndrome (IBS) Download English PDF, 952KB, PDFIrritable bowel syndrome (IBS) is a chronic (long-term) condition that affects the large instestine. It may cause abdominal pain because of abnormal contractions and problems with bowel movements.Work closely with your doctor to monitor your symptoms over time. Your doctor may recommend further testing if your symptoms change. [Please download the PDF file if you are unable to view the image below.]