Irritable bowel syndrome Health Article

Definition

Irritable bowel syndrome (IBS) refers to a disorder of the lower intestinal tract. It involves abdominal pain and abnormal bowel movements. Emotional stress often makes the symptoms worse.

It is not the same as inflammatory bowel disease (IBD), which includes Crohn's disease and ulcerative colitis.

Alternative Names

Nervous indigestion; Spastic colon; Intestinal neurosis; Functional colitis; Irritable colon; Mucous colitis; Laxative colitis; IBS

Causes, incidence, and risk factors

IBS involves a combination of abdominal pain and constipation, diarrhea, or an alternating pattern of these problems.

There are many possible causes. For example, there may be a problem with muscle movement in the intestine or a lower tolerance for stretching and movement of the intestine. There is no problem with the structure of the intestine.

It is not clear why patients develop IBS, but in some instances, it occurs after an intestinal infection. This is called postinfectious IBS. There may also be other triggers.

IBS can occur at any age, but it often begins in adolescence or early adulthood. It is more common in women. The condition is the most common intestinal complaint for which patients are referred to a gastroenterologist.

Symptoms

Symptoms range from mild to severe. Most people have mild symptoms. IBS symptoms may be worse in patients who also have stress or mood disorders, such as anxiety and depression. However, it is important to understand that these conditions do not cause IBS.

Symptoms may include:

• Abdominal distention
• Abdominal fullness, gas, bloating
• Abdominal pain that:
  • Comes and goes
  • Is reduced or goes away after a bowel movement
  • Occurs after meals
• Chronic and frequent constipation, usually accompanied by pain
• Chronic and frequent diarrhea, usually accompanied by pain
• Emotional distress
• Depression
• Loss of appetite