I have constipation and each time I have to strain a lot. I do not have any abdominal pain or other symptoms. Do I have IBS?

Dr. Drossman: Irritable bowel syndrome (IBS) is diagnosed when there is a combination of symptoms, specifically abdominal pain with usually diarrhea, constipation or at times, both. You say you have constipation, and if that is associated with pain, you may have IBS. If you don’t have pain or if you have pain that is not associated with your constipation, you may have what is called functional constipation. People with symptoms of constipation who need to strain may do so for two possible reasons. The first is that when stools are very hard and in small pieces, it is difficult to easily expel the stool and often the person must strain to evacuate. Another possibility can be when the muscles in the pelvic floor don’t relax properly. This is called pelvic floor dysfunction or pelvic floor dyssynergia. In this case, one of the pelvic floor muscle groups, called the puborectalis, remains tense when it should relax during defecation, and this keeps the passageway narrow and at an angle thus preventing stool from passing through the rectum. In fact, the more one strains, the more acute the angle and the more tense the muscle becomes. Your gastroenterologist can make this diagnosis with a rectal examination and a special procedure called anorectal motility. If present, the condition can be treated using a type of biofeedback that teaches you through exercises to relax this muscle and ultimately reduce the straining.