Irritable bowel syndrome is a disorder that affects the lower digestive system, mainly the colon and rectum, causing great discomfort in the form of abdominal pain, bloating, constipation, cramping, or diarrhea. Luckily, though the discomforts are great, they will not cause serious harm. IBS flares when you eat the wrong diet. Stress can cause it to flare up as well. IBS, if untreated, is debilitating, causing a person to stick close to home, unable to hold down a job or do anything away from home. The good news is that IBS is very treatable and manageable with medications, diet and stress management.