Irritable bowel syndrome (IBS) Introduction Irritable bowel syndrome (IBS) is a common, long-term condition of the digestive system. It can cause bouts of stomach cramps, bloating, diarrhoea and/or constipation. IBS is thought to affect up to 1 in 5 people at some point in their life, and it usually first develops when a person is between 20 and 30 years of age. Around twice as many women are affected as men. The condition is often life long, although it may improve over several years. Irritable bowel syndrome (IBS) is a problem that affects the large intestine. It can cause abdominal cramping, bloating, and a change in bowel habits. Some people with the disorder have constipation. Some have diarrhea. Others go back and forth between the two. Although IBS can cause a great deal of discomfort, it does not harm the intestines. IBS is common. It affects about twice as many women as men and is most often found in people younger than 45 years. No one knows the exact
