Constipation

Normal bowel function ranges from 3 bowel movements a day to one bowel movement every 3 days. Constipation is having bowel movements infrequently which are hard and difficult to pass. Other symptoms of constipation include abdominal bloating, cramping and pelvic pain or pressure.

Generally speaking there are 2 main categories of constipation

1. Colonic inertia – this is a dymotility condition of the colon. The colon is not effective at moving stool along to the rectum.
2. Obstructive defecation – this is a functional disorder of the rectum. The colon is able to move stool normally to the rectum but an abnormality of the pelvic floor and rectum make it difficult to evacuate the stool.

There are many causes of constipation as listed below:

• Lack of daily water and fiber intake
• Pelvic floor dysfunction
• Blockages of the colon and rectum from diseases like diverticulitis, Crohn’s disease, or cancer
• Nerve damage from conditions like diabetes, multiple sclerosis, Parkinson’s disease, spinal cord injury, or strokes
• Medical conditions like diabetes, low thyroid function, high parathroyid function, and pregnancy
• Medications such as opioids

Straining is the use of abdominal muscles to increase intraabdominal pressure to help force the evacuation of stool. Short bursts of straining are often used to initiate a bowel movement; however, prolonged and forceful straining can result in increasing difficulty to emptying your bowels.

Under normal conditions, the pelvic floor muscles and sphincter muscles are contracted to help maintain continence and during a bowel movement, those muscles relax to allow for the passage or evacuation of stool. During straining, all of the pelvic floor muscles contract making it more difficult to empty your rectum. Additionally, the brain senses the need for a bowel movement when pressure is applied to the pelvic floor. Straining increases the pressure on the pelvic floor so the sensation is incomplete evaluation regardless of the amount of stool that is actually passed. The more straining there is the more pronounced these symptoms may become.

Constipation can be experienced by bowel movements that are infrequent, painful and/or difficult to pass. They can be associated with bleeding related to conditions such as hemorrhoids or anal fissures, however all rectal bleeding should be evaluated by a physician.

Patients can have significant pelvic, abdominal, or back pain with constipation. Straining and difficulty to pass stool, along with feelings of not being completely empty after a bowel movement, can also be symptoms of constipation. Some patients may experience significant abdominal fullness to the point of nausea.

Evaluation of constipation should start with a complete medical history performed by your physician to identify contributing medical conditions or medications. A physical examination is done which may include a rectal examination, a vaginal examination, and possibly an internal rectal exam using an anoscope. An anoscope is a small lighted instrument that looks at the lowest part of the anal canal to assess for hemorrhoids, fissures, inflammation, or narrowing which may be associated with constipation.

Additional testing may include a scope exam done with or without anesthesia such as proctoscopy, flexible sigmoidoscopy, or colonoscopy. Other tests that look at the function of the colon (colonic transit study) or the function of the anorectal region and pelvic floor, such as a defecography, anal manometry, anal electromyography, or anal ultrasound, may also be performed. The evaluations helps to identify if the issue is related the function of the colon or the rectum/pelvic floor.

There are many things that can be done to treat constipation. The first step begins with diet and lifestyle changes. This means increasing your daily fiber intake by eating fruits and vegetables and lowering your daily fat intake. It is very important to drink 64 oz of a non-caffeinated beverage daily and avoid excessive amounts of alcohol and caffeine.

A healthy exercise program is also important to improve the activity of your bowels and allow for more frequent bowel movements. These lifestyle changes not only help constipation but a number of other medical issues many patients may be experiencing and will improve overall health and quality of life.

There are many types of medications that can be taken to improve bowel function. Over the counter fiber supplements are safe and work well to help with symptoms of constipation by adding bulk to the stool and making them easier to pass. Stool softeners also safe and effective in helping with bowel function. There are numerous over the counter and prescription laxatives that are available such as stimulants (Dulcolax, Senokot, Ex-Lax), osmotic laxatives (Milk of Magnesia, magnesium citrate, lactulose, Miralax, Glycolax), and lubricant laxatives (mineral oil). Enemas and suppositories may also be of benefit. If these medications do not provide relief, your doctor may suggest a stronger laxative available by prescription.

Pelvic floor dysfunction may also be a strong contributor of constipation and retraining your pelvic floor muscles may be very beneficial in controlling symptoms. Pelvic floor physical therapists utilize many tools such as biofeedback, positional maneuvers, and massage therapy to help improve bowel frequency and decrease symptoms.

Surgery may also be indicated to remove the colon for some types of constipation. The primary focus of all treatments are to improve bowel function and minimize the associated symptoms. Normal bowel function is a very wide range so understanding the expected results of the treatments is very important to improving your overall results and satisfaction.

Washington University Colorectal can provide options and treatments for constipation. Meet our specialists below. 

Kerri Ohman, MD

Paul Wise, MD

Steven Hunt, MD

Matthew Silviera, MD

Matthew Mutch, MD