What can I do for my chronic constipation?

Conditions Expert Dr. Otis Brawley Chief Medical Officer,
American Cancer Society

Expert answer

I strongly recommend you consult a gastroenterologist. Chronic constipation is the most common digestive complaint and is associated with significant economic costs. For most people it is a mild inconvenience. For a few it can be a serious problem. Most with this malady would do better by simply eating the recommended five to nine servings of fruits and vegetables per day, drinking at least 60 ounces of water per day and getting some exercise, even walking. Some with more severe and chronic constipation would benefit from additional fiber in the diet. We often suggest Metamucil or fiber bars.

Let me give you an idea of how constipation is addressed after those interventions have not solved the problem. First, there are varied meanings to the term constipation and the physician would have to find out just what the patient means. Some people will complain of stool being too hard, too small, or that having a bowel movement is too difficult or occurs infrequently. These are clues. Several years ago, a committee of gastroenterologists came together to create a definition and criteria for constipation. The result is called the Rome III Criteria. It helps us approach this problem in a more rigorous and scientific way.

In essence, constipation is when stool does not move through the colon or anorectum -- the distal portion of the digestive tract, including the entire anal canal -- in an ordered way. The colon or large bowel is a long tube, 4 to 6 feet in length in most adults. There are muscles in the colonic wall. These muscles contract in an ordered way to propel the waste matter. There can be dysfunction caused by a motor disorder, meaning that the muscles of the colon walls do not propel food adequately, the stool is too hard or there is a physical obstruction of the large bowel.

A nerve problem or neurogenic disorder may prevent the muscles from contracting in an ordered sequence. Common causes of neurogenic bowel disease in adults include diabetes mellitus, multiple sclerosis or Parkinson's disease. Spinal cord injury can also cause constipation.

Non-neurogenic causes of bowel muscle dysfunction include low thyroid dysfunction, pituitary failure or low serum potassium. High blood calcium levels, which can result from an overactive parathyroid or several cancers, can also be a non-neurogenic cause of constipation. Certain muscle diseases such as myotonic dystrophy occasionally cause constipation.

Drugs that can cause constipation include analgesics, especially opiate pain medicine, cold medicines such as antihistamines, antidepressants and anti-pschycotics. Iron supplements can also cause constipation. Several anti-hypertensive drugs are famous for causing constipation through dehydrating and hardening stool and interfering with nerve conduction to bowel wall muscle.

A physician will review known diagnoses and the drugs a patient is taking. Blood studies to assess electrolytes and thyroid function are commonly done. If there is any suspicion of a partial bowel obstruction from a developmental defect, a prior abdominal surgery, a polyp or a colon cancer, a scoping procedure to evaluate the colon and possibly a barium X-ray study of the bowel will be done.