Irritable bowel syndrome (IBS) is a group of symptoms that cause digestive, abdominal discomfort and/or changes in the pattern of bowel movements without any evidence of underlying damage. It is what doctors call a functional disease. Someone with this type of disease will have a group of symptoms, but tests won’t show any physical explanation for those problems. IBS will not increase your risk of developing bowel cancer. IBS has evolved into a very common gastrointestinal disorder that affects 1 in 7 people. The causes are not well understood, and it is diagnosed based on ruling out other conditions with similar symptoms. Diet and lifestyle modifications are the best option at present, and some medications may help as well. IBS is a chronic condition that can be controlled, but not cured.
At its core, Irritable Bowel Syndrome causes irritation because it affects the function and behavior of the intestines. Normally, the muscles lining the intestines contract and relax to move food along the digestive tract. In IBS, this pattern is disturbed, resulting in uncomfortable symptoms. In addition, there can be a disturbance in sensation, with heightened sensitivity to normal gas or stool passing through the GI tract.
IBS related symptoms may occur over a long time, often years, and classic symptoms such as abdominal pain and abnormal bowel habits may be accompanied by abdominal bloating, increase in abdominal girth (distension), excessive gas, urgency to defecate, and fatigue. Symptoms usually are experienced as acute attacks that subside within one day, but recurrent attacks are likely. There may also be urgency for bowel movements and a feeling of incomplete evacuation (tenesmus). It is common for the symptoms of IBS to fluctuate over time – there are good times and bad times. IBS symptoms can vary greatly between individuals and they might vary over time.
Many people experience mild symptoms of IBS, but for some, symptoms can be severe. Symptoms can include cramping, abdominal pain, bloating, gas, mucus in the stool, diarrhea, and/or constipation.
“Symptoms and Causes of Irritable Bowel Syndrome”. NIDDK. February 23, 2015.