What Could Cause CIC?

Part of having chronic idiopathic constipation is that there may not be a direct cause found. In fact, that's what "idiopathic" in the name means.

However, in some cases, one of three things may be causing the symptoms.

Low Motility

Motility refers to how food is moved through the body by the gastrointestinal tract and becomes digested and expelled. When motility is slowed down, waste moves more slowly through the body, which could lead to having hard stools that are difficult to pass. Stools from low motility may be like pellets or nuts or could be sausage-shaped, but lumpy.

In some cases, specialized tests might be used to track how long it takes to digest food. In most cases, however, after a thorough discussion of health history, the hard or lumpy stools along with negative results from a rectal exam are enough to diagnose low motility.

Pelvic Floor Dysfunction

An abnormality in the pelvic floor is another potential cause of CIC. The pelvic floor includes all the structures (muscles, ligaments, and nerves) that support the organs in the pelvis, such as the bladder and rectum, as well as the uterus and vagina in women.

If the muscles in the pelvic floor are not working well to expel stool, constipation could be the result. Some people with CIC may have a loss of sensation in their rectum and therefore may not feel a strong urge to go to the bathroom.

Pelvic floor dysfunction may also cause feeling like a bowel movement isn't complete, straining during a bowel movement, discomfort or pain in the pelvic area or the back. Less commonly, there could be a structural problem, such as a rectal prolapse or a hernia, causing the constipation.

To diagnose pelvic floor dysfunction, a physician will take a careful history, asking about problems with the bladder or the bowel. A physical exam is done to look for any problems with the muscles, such as weakness or spasms. A physician might also test muscles during a test where electrodes are applied to the skin. Less commonly, a special kind of x-ray might be used to observe the muscles in the rectum or a another test might be done to measure urine flow.  

Pelvic floor dysfunction sounds scary, but the good news is that it is very treatable and treatment is usually successful. In most cases, non-invasive therapies such as biofeedback (learning to voluntarily control the pelvic floor muscles) and physical therapy can help resolve the constipation and improve quality of life.


Many prescription and over-the-counter medications can lead to constipation. If you experience constipation after you begin to take a certain medication, the doctor that prescribed the drug will need to know so that you can both decide how best to proceed.

Some of the medications often associated with constipation include:

  • Antacids that contain aluminum: Aluminum slows down the muscle activity in the stomach and intestine
  • Antidepressants: Tricyclic antidepressants cause the muscles in the intestine to slow down and decreases intestinal fluids
  • Antihistamines (such as diphenhydramine): Antihistamines may slow down body processes
  • Blood pressure medications (particularly diuretics): Diuretics cause the body to lose fluids, which may cause dehydration and constipation
  • Iron supplements: Iron supplements cause more water to be absorbed by the large intestine and stools become harder
  • Pain killers (narcotics): Narcotics cause the bowel to slow down, and stool takes longer to pass through

When the Cause Is Unknown

Having constipation that's from an idiopathic, or an unknown, cause can be distressing. However, even though the underlying cause might not be diagnosed, there are still effective treatments that can help resolve the symptoms.

For some people, it may take time to get a diagnosis, and a bit of persistence could be necessary. Working closely with healthcare providers to try different approaches, including diet, lifestyle changes, and medications, often works well to help with the symptoms of constipation. The understanding of constipation is improving, which offers hope for more efficiency in diagnosis and more effective treatments.