Constipation in Adults

What is it?

Constipation is disordered movement of stool through the colon or anus and rectum. It may include at least two of the following symptoms:

Passing a bowel movement less than three times per week
Lumpy or hard stools
Straining to pass a bowel movement
A feeling of obstruction, blockage or incomplete evacuation
Using your hands to help pass a bowel movement
Rarely having loose stools without the use of laxatives.

Who gets it?

Constipation is a common problem. Constipation becomes an issue for more people as they age.

Why does it happen?

The muscle function of the colon, anus and rectum is coordinated by both the enteric nervous system (present in the gut), and the central nervous system (the brain and spinal cord).

Constipation can be a side effect of commonly used drugs. It can be related to other disorders such as; metabolic disorders like diabetes, or thyroid problems, issues with the nervous system, or obstruction of the intestine. Sometimes, the cause is unknown.

Symptoms can be mild or severe.

How is it diagnosed?

Evaluation will start with a discussion and physical exam. It is important to determine what your bowel pattern is like; if there has been a change in your bowel habits. Keeping a journal of bowel movements is helpful. It is important to note any recent medications that have been started, as constipation often is linked to new medicines. Treatment may start with education, and a trial of dietary changes and fiber. If this fails, studies may be performed such as; blood work, imaging or transit studies. A transit study can be performed by swallowing markers that show up on x-rays to determine the speed of stool moving through your colon. Colonoscopy may be recommended.

How is it treated?

If a medication or treatable cause is identified as the source of your constipation, it will be removed or treated. Regular trials of a bowel movement in the morning and after meals may be recommended, as this is when there are the highest levels of movement in the colon.

Diet is addressed. Increasing the amount of fiber eaten, while increasing water intake can provide improvement. Fiber supplements can also be taken; the goal is to consume 20-35 grams per day. Fiber may increase bloating and flatulence. So start with small amounts of fiber and slowly increase.

Bulk-forming fiber supplements such as psyllium (Metamucil), methylcellulose (Citrucel), calcium polycarbophil (FiberCon), and wheat dextran (Benefiber) absorb water in the colon.

This causes more mass to the bowel movement and softer, more frequent stools.

There are many other types of laxatives. Sometimes, choice is dependent on cost or preferences.

Osmotic agents. These medications contain sugars or salts that are not well absorbed, so water is drawn into the colon. Examples are:
- Polyethylene glycol
- In solution form (GoLYTELY) or powdered (MiraLAX)

Synthetic carbohydrate
- Lactulose (Enulose), this requires 1-2 days to work
- Sorbitol

Saline laxative
- Milk of magnesiaMagnesium citrate

Surfactants. These are stool softeners working to lower the surface tension of stool so then water can enter the stool. An example is docusate sodium (Colace).

Stimulants. These medications change how electrolytes are moved through the tissue of the colon and increase movement. Daily consumption of stimulant laxatives can lead to low blood levels of potassium, abnormal loss of protein from the GI tract and salt overload so these medications should be taken with caution. Examples are:

Bisacodyl
Senna
Sodium picosulfate

Other options may be considered such as:

Suppositories. These are little bullet-shaped medications that are inserted into the rectum and can cause stool in the rectum to become more liquid and stimulate passage.
Blockage in the rectum with a large bulk of stool should be removed manually. An enema may be given; often with mineral oil, so the stool will be softened and lubricated. If this is not successful for the complete passage of stool, a different type of enema can be given with fluoroscopy. (This will be performed to look for a cause of obstruction.) Sometimes, the colon will be completely emptied. This can be done with enemas daily for several days, or drinking a bowel preparation solution.
After getting the stool cleaned out, maintaining a regular bowel pattern is very important. It can be accomplished with using one of the osmotic agents above, with the goal of passing stool at least every other day. If there is no stool in two days, a suppository can be used to prevent another impaction.

Behavioral methods can also be attempted such as biofeedback. This is usually completed at a specialty clinic.

Other medications have also been used such as:

A medication called Lubiprostone (Amitiza) may be considered. This drug works on specific channels in the colon that secrete fluid. Common side effects are nausea and diarrhea.

Rarely, surgery with removal of most of the colon can be considered. Five criteria are typically met before surgery is considered:

1. 1. Severe symptoms that do not respond to medical treatment
2. 2. Slow movement in the colon of stool on transit studies
3. 3. There is not a pseudoobstruction
4. 4. Anorectal manometry does not show pelvic floor dysfunction
5. 5. Abdominal pain is not the most significant symptom