Medical Author:

John P. Cunha, DO, FACOEP

John P. Cunha, DO, FACOEP

John P. Cunha, DO, is a U.S. board-certified Emergency Medicine Physician. Dr. Cunha's educational background includes a BS in Biology from Rutgers, the State University of New Jersey, and a DO from the Kansas City University of Medicine and Biosciences in Kansas City, MO. He completed residency training in Emergency Medicine at Newark Beth Israel Medical Center in Newark, New Jersey.

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Medical Editor:

Jay W. Marks, MD

Jay W. Marks, MD

Jay W. Marks, MD, is a board-certified internist and gastroenterologist. He graduated from Yale University School of Medicine and trained in internal medicine and gastroenterology at UCLA/Cedars-Sinai Medical Center in Los Angeles.

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What is constipation?

Constipation is a condition that is characterized by infrequent bowel movements that are painful or difficult, or stools that are hard in consistency. Infrequent bowel movements alone are not a reliable indicator of constipation because bowel frequency can vary between three times a day to once a week among normal individuals. Hard stools that are difficult to pass or infrequent stools accompanied by abdominal pain, back pain, and abdominal bloating define constipation.

What are the causes of constipation?

There are many causes of constipation including:

• Diets low in fiber. Fiber is vegetable material resistant to digestion that promotes soft stools by adding bulk to the stool and causing water to be retained in stool.
• Side effects of medications such as narcotic painkillers, antidepressants, iron supplements, calcium channel blockers (medications for high blood pressure), and certain types of antacids.
• Narrowing or blockage of the large intestine (colon) due to scarring from previous surgery, colon cancer or advanced diverticulosis.
• Ineffective contraction or spasm of the colon's muscles due to irritable bowel syndrome (IBS) or other diseases of the colon's muscles.
• Hormonal (endocrine) disturbances such as an underactive thyroid gland (hypothyroid) and diabetes mellitus with nerve damage.
• Neurologic conditions such as Parkinson's disease, multiple sclerosis, and others.

Examples of common medications that can cause constipation:

• Narcotic pain medications: codeine (Tylenol #3), oxycodone (Percocet), guaifenesin/hydromorphone (Dilaudid), and others
• Antidepressants: amitriptyline (Elavil, Endep), fluoxetine (Prozac), and imipramine (Tofranil)
• Anticonvulsants: phenytoin (Dilantin) and carbamazepine (Tegretol)
• Iron supplements
• Calcium channel blockers (for example, diltiazem [Cardizem] and nifedipine [Procardia])
• Antacids (for example, aluminum hydroxide [Amphojel] and aluminum carbonate [Basaljel])