Dr. MJ Bazos MD,
Constipation is passage of small amounts of
hard, dry bowel movements, usually fewer than three times a week. People who are
constipated may find it difficult and painful to have a bowel movement. Other
symptoms of constipation include feeling bloated, uncomfortable, and sluggish.
Many people think they are constipated
when, in fact, their bowel movements are regular. For example, some people
believe they are constipated, or irregular, if they do not have a bowel movement
every day. However, there is no right number of daily or weekly bowel movements.
Normal may be three times a day or three times a week depending on the person.
In addition, some people naturally have firmer stools than others.
At one time or another almost everyone
gets constipated. Poor diet and lack of exercise are usually the causes. In most
cases, constipation is temporary and not serious. Understanding causes,
prevention, and treatment will help most people find relief.
Who Gets Constipated?
According to the 1991 National Health
Interview Survey, about 4 1/2 million people in the United States say they are
constipated most or all of the time. Those reporting constipation most often are
women, children, and adults age 65 and over. Pregnant women also complain of
constipation, and it is a common problem following childbirth or surgery.
Constipation is the most common
gastrointestinal complaint in the United States, resulting in about 2 million
annual visits to the doctor. However, most people treat themselves without
seeking medical help, as is evident from the $725 million Americans spend on
laxatives each year.
constipation, it helps to know how the colon (large intestine) works. As food
moves through it, the colon absorbs water while forming waste products, or
stool. Muscle contractions in the colon push the stool toward the rectum. By the
time stool reaches the rectum, it is solid because most of the water has been
The hard and dry stools of
constipation occur when the colon absorbs too much water. This happens because
the colon's muscle contractions are slow or sluggish, causing the stool to move
through the colon too slowly.Listed below are the most common causes of
Common Causes of
- Not enough fiber in diet
- Not enough liquids
- Lack of exercise
- Irritable bowel syndrome
- Changes in life or routine such as pregnancy,
older age, and travel
- Abuse of laxatives
- Ignoring the urge to have a bowel movement
- Specific diseases such as multiple sclerosis and
- Problems with the colon and rectum
- Problems with intestinal function (Chronic
The most common cause of constipation
is a diet low in fiber found in vegetables, fruits, and whole grains and high in
fats found in cheese, eggs, and meats. People who eat plenty of high-fiber foods
are less likely to become constipated.
insoluble—is the part of fruits, vegetables, and grains that the body
cannot digest. Soluble fiber dissolves easily in water and takes on a soft,
gel-like texture in the intestines. Insoluble fiber passes almost unchanged
through the intestines. The bulk and soft texture of fiber help prevent hard,
dry stools that are difficult to pass.
On average, Americans eat about 5 to
20 grams of fiber daily, short of the 20 to 35 grams recommended by the American
Dietetic Association. Both children and adults eat too many refined and
processed foods in which the natural fiber is removed.
A low-fiber diet also plays a key role in
constipation among older adults. They often lack interest in eating and may
choose fast foods low in fiber. In addition, loss of teeth may force older
people to eat soft foods that are processed and low in fiber.
Not Enough Liquids
Liquids like water and juice add fluid
to the colon and bulk to stools, making bowel movements softer and easier to
pass. People who have problems with constipation should drink enough of these
liquids every day, about eight 8-ounce glasses. Other liquids, like coffee and
soft drinks, that contain caffeine seem to have a dehydrating effect.
Lack of Exercise
Lack of exercise can lead to
constipation, although doctors do not know precisely why. For example,
constipation often occurs after an accident or during an illness when one must
stay in bed and cannot exercise.
Pain medications (especially
narcotics), antacids that contain aluminum, antispasmodics, antidepressants,
iron supplements, diuretics, and anticonvulsants for epilepsy can slow passage
of bowel movements.
Some people with IBS,
also known as spastic colon, have spasms in the colon that affect bowel
movements. Constipation and diarrhea often alternate, and abdominal cramping,
gassiness, and bloating are other common complaints. Although IBS can produce
lifelong symptoms, it is not a life-threatening condition. It often worsens with
stress, but there is no specific cause or anything unusual that the doctor can
see in the colon.
Changes in Life
During pregnancy, women may
be constipated because of hormonal changes or because the heavy uterus
compresses the intestine. Aging may also affect bowel regularity because a
slower metabolism results in less intestinal activity and muscle tone. In
addition, people often become constipated when traveling because their normal
diet and daily routines are disrupted.
Abuse of Laxatives
Myths about constipation have led to a
serious abuse of laxatives. This is common among older adults who are
preoccupied with having a daily bowel movement.
Laxatives usually are not necessary
and can be habit-forming. The colon begins to rely on laxatives to bring on
bowel movements. Over time, laxatives can damage nerve cells in the colon and
interfere with the colon's natural ability to contract. For the same reason,
regular use of enemas can also lead to a loss of normal bowel function.
Ignoring the Urge to Have a Bowel
People who ignore the urge to
have a bowel movement may eventually stop feeling the urge, which can lead to
constipation. Some people delay having a bowel movement because they do not want
to use toilets outside the home. Others ignore the urge because of emotional
stress or because they are too busy. Children may postpone having a bowel
movement because of stressful toilet training or because they do not want to
interrupt their play.
Diseases that cause
constipation include neurological disorders, metabolic and endocrine disorders,
and systemic conditions that affect organ systems. These disorders can slow the
movement of stool through the colon, rectum, or anus. Listed below are the
diseases that cause constipation.
Diseases That Cause Constipation
Neurological disorders that
may cause constipation include:
•Chronic idiopathic intestinal
•Spinal cord injuries.
Metabolic and endocrine
•Underactive or overactive thyroid gland
Systemic disorders include:
Problems with the Colon and Rectum
- Intestinal obstruction,
- Scar tissue (adhesions),
- Colorectal stricture,
- Hirschsprung's disease, or
- Cancer can compress, squeeze, or narrow the
intestine and rectum and cause constipation.
Problems with Intestinal
Function (Chronic Idiopathic Constipation)
Also known as functional constipation,
chronic idiopathic (of unknown origin) constipation is rare. However, some
people are chronically constipated and do not respond to standard treatment.
This chronic constipation may be related to multiple problems with hormonal
control or with nerves and muscles in the colon, rectum, or anus. Functional
constipation occurs in both children and adults and is most common in women.
Colonic inertia and delayed
transit are two types of functional constipation caused by decreased muscle
activity in the colon. These syndromes may affect the entire colon or may be
confined to the left or lower (sigmoid) colon.
Functional constipation that stems
from abnormalities in the structure of the anus and rectum is known as anorectal
dysfunction, or anismus. These abnormalities result in an inability to relax the
rectal and anal muscles that allow stool to exit.
What Diagnostic Tests Are Used?
Most people do not need extensive
testing and can be treated with changes in diet and exercise. For example, in
young people with mild symptoms, a medical history and physical examination may
be all the doctor needs to suggest successful treatment. The tests the doctor
performs depends on the duration and severity of the constipation, the person's
age, and whether there is blood in stools, recent changes in bowel movements, or
The doctor may ask a patient to
describe his or her constipation, including duration of symptoms, frequency of
bowel movements, consistency of stools, presence of blood in the stool, and
toilet habits (how often and where one has bowel movements). Recording eating
habits, medication, and level of physical activity or exercise also helps the
doctor determine the cause of constipation.
A physical exam may include a digital
rectal exam with a gloved, lubricated finger to evaluate the tone of the muscle
that closes off the anus (anal sphincter) and to detect tenderness, obstruction,
or blood. In some cases, blood and thyroid tests may be necessary.
Extensive testing usually is reserved
for people with severe symptoms, for those with sudden changes in number and
consistency of bowel movements or blood in the stool, and for older adults.
Because of an increased risk of colorectal cancer in older adults, the doctor
may use these tests to rule out a diagnosis of cancer:
•Barium enema x-ray
•Sigmoidoscopy or colonoscopy
•Colorectal transit study
•Anorectal function tests.
Barium Enema X-Ray
A barium enema x-ray involves viewing
the rectum, colon, and lower part of the small intestine to locate any problems.
This part of the digestive tract is known as the bowel. This test may show
intestinal obstruction and Hirschsprung's disease, a lack of nerves within the
The night before the test,
bowel cleansing, also called bowel prep, is necessary to clear the lower
digestive tract. The patient drinks 8 ounces of a special liquid every 15
minutes for about 4 hours. This liquid flushes out the bowel. A clean bowel is
important, because even a small amount of stool in the colon can hide details
and result in an inaccurate exam.
the colon does not show up well on an x-ray, the doctor fills the organs with a
barium enema, a chalky liquid to make the area visible. Once the mixture coats
the organs, x-rays are taken that reveal their shape and condition. The patient
may feel some abdominal cramping when the barium fills the colon, but usually
feels little discomfort after the procedure. Stools may be a whitish color for a
few days after the exam.
Sigmoidoscopy or Colonoscopy
An examination of the rectum and lower
colon (sigmoid) is called a sigmoidoscopy. An examination of the rectum and
entire colon is called a colonoscopy.
night before a sigmoidoscopy, the patient usually has a liquid dinner and takes
an enema at bedtime. A light breakfast and a cleansing enema an hour before the
test may also be necessary.
To perform a
sigmoidoscopy, the doctor uses a long, flexible tube with a light on the end
called a sigmoidoscope to view the rectum and lower colon. First, the doctor
examines the rectum with a gloved, lubricated finger. Then, the sigmoidoscope is
inserted through the anus into the rectum and lower colon. The procedure may
cause a mild sensation of wanting to move the bowels and abdominal pressure.
Sometimes the doctor fills the organs with air to get a better view. The air may
cause mild cramping.
To perform a
colonoscopy, the doctor uses a flexible tube with a light on the end called a
colonoscope to view the entire colon. This tube is longer than a sigmoidoscope.
The same bowel cleansing used for the barium x-ray is needed to clear the bowel
of waste. The patient is lightly sedated before the exam. During the exam, the
patient lies on his or her side and the doctor inserts the tube through the anus
and rectum into the colon. If an abnormality is seen, the doctor can use the
colonoscope to remove a small piece of tissue for examination (biopsy). The
patient may feel gassy and bloated after the procedure.
Colorectal Transit Study
This test, reserved for those with
chronic constipation, shows how well food moves through the colon. The patient
swallows capsules containing small markers, which are visible on x-ray. The
movement of the markers through the colon is monitored with abdominal x-rays
taken several times 3 to 7 days after the capsule is swallowed. The patient
follows a high-fiber diet during the course of this test.
Anorectal Function Tests
These tests diagnose constipation
caused by abnormal functioning of the anus or rectum (anorectal function).
Anorectal manometry evaluates anal sphincter muscle function. A catheter or
air-filled balloon inserted into the anus is slowly pulled back through the
sphincter muscle to measure muscle tone and contractions.
Defecography is an x-ray of the anorectal
area that evaluates completeness of stool elimination, identifies anorectal
abnormalities, and evaluates rectal muscle contractions and relaxation. During
the exam, the doctor fills the rectum with a soft paste that is the same
consistency as stool. The patient sits on a toilet positioned inside an x-ray
machine and then relaxes and squeezes the anus and expels the solution. The
doctor studies the x-rays for anorectal problems that occurred while the patient
emptied the paste.
treatment depends on the cause, severity, and duration, in most cases dietary
and lifestyle changes will help relieve symptoms and help prevent constipation.
A diet with enough fiber (20 to 35
grams each day) helps form soft, bulky stool. A doctor or dietitian can help
plan an appropriate diet. High-fiber foods include beans; whole grains and bran
cereals; fresh fruits; and vegetables such as asparagus, brussels sprouts,
cabbage, and carrots. For people prone to constipation, limiting foods that have
little or no fiber such as ice cream, cheese, meat, and processed foods is also
Other changes that can help treat and
prevent constipation include drinking enough water and other liquids such as
fruit and vegetable juices and clear soup, engaging in daily exercise, and
reserving enough time to have a bowel movement. In addition, the urge to have a
bowel movement should not be ignored.
Most people who are mildly constipated
do not need laxatives. However, for those who have made lifestyle changes and
are still constipated, doctors may recommend laxatives or enemas for a limited
time. These treatments can help retrain a chronically sluggish bowel. For
children, short-term treatment with laxatives, along with retraining to
establish regular bowel habits, also helps prevent constipation.
A doctor should determine when a
patient needs a laxative and which form is best. Laxatives taken by mouth are
available in liquid, tablet, gum, powder, and granule forms. They work in
laxatives generally are considered the safest but can interfere with
absorption of some medicines. These laxatives, also known as fiber supplements,
are taken with water. They absorb water in the intestine and make the stool
softer. Brand names include Metamucil®, Citrucel®, and Serutan®.
•Stimulants cause rhythmic
muscle contractions in the intestines. Brand names include Correctol®,
Dulcolax®, Purge®, Feen-A-Mint®, and Senokot®. Studies suggest
that phenolphthalein, an ingredient in some stimulant laxatives, might increase
a person's risk for cancer. The Food and Drug Administration has proposed a ban
on all over-the-counter products containing phenolphthalein. Most laxative
makers have replaced or plan to replace phenolphthalein with a safer ingredient.
•Stool softeners provide
moisture to the stool and prevent dehydration. These laxatives are often
recommended after childbirth or surgery. Products include Colace®,
Dialose®, and Surfak®.
•Lubricants grease the stool
enabling it to move through the intestine more easily. Mineral oil is the most
laxatives act like a sponge to draw water into the colon for easier passage
of stool. Laxatives in this group include Milk of Magnesia®, Citrate of
Magnesia®, and Haley's M-O®.
People who are dependent on laxatives
need to slowly stop using the medications. A doctor can assist in this process.
In most people, this restores the colon's natural ability to contract.
Treatment may be directed at a specific
cause. For example, the doctor may recommend discontinuing medication or
performing surgery to correct an anorectal problem such as rectal prolapse.
People with chronic constipation
caused by anorectal dysfunction can use biofeedback to retrain the muscles that
control release of bowel movements. Biofeedback involves using a sensor to
monitor muscle activity that at the same time can be displayed on a computer
screen allowing for an accurate assessment of body functions. A health care
professional uses this information to help the patient learn how to use these
Surgical removal of the colon
may be an option for people with severe symptoms caused by colonic inertia.
However, the benefits of this surgery must be weighed against possible
complications, which include abdominal pain and diarrhea.
Can Constipation Be Serious?
Sometimes constipation can lead to
complications. These complications include hemorrhoids caused by straining to
have a bowel movement or anal fissures (tears in the skin around the anus)
caused when hard stool stretches the sphincter muscle. As a result, rectal
bleeding may occur that appears as bright red streaks on the surface of the
stool. Treatment for hemorrhoids may include warm tub baths, ice packs, and
application of a cream to the affected area. Treatment for anal fissure may
include stretching the sphincter muscle or surgical removal of tissue or skin in
the affected area.
causes a small amount of intestinal lining to push out from the anal opening.
This condition is known as rectal prolapse and may lead to secretion of mucus
from the anus. Usually, eliminating the cause of the prolapse such as straining
or coughing is the only treatment necessary. Severe or chronic prolapse requires
surgery to strengthen and tighten the anal sphincter muscle or to repair the
also cause hard stool to pack the intestine and rectum so tightly that the
normal pushing action of the colon is not enough to expel the stool. This
condition, called fecal impaction, occurs most often in children and older
adults. An impaction can be softened with mineral oil taken by mouth and an
enema. After softening the impaction, the doctor may break up and remove part of
the hardened stool by inserting one or two fingers in the anus.
Points to Remember
1. Constipation affects almost
everyone at one time or another.
people think they are constipated when, in fact, their bowel movements are
3. The most common causes of
constipation are poor diet and lack of exercise.
4. Additional causes of constipation
include medications, irritable bowel syndrome, abuse of laxatives, and specific
5. A medical history and
physical examination may be the only diagnostic tests needed before the doctor
6. In most cases,
following these simple tips will help relieve symptoms and prevent recurrence
- Eat a well-balanced, high-fiber diet that
includes beans, bran, whole grains, fresh fruits, and vegetables.
- Drink plenty of liquids.
- Exercise regularly.
- Set aside time after breakfast or dinner for
undisturbed visits to the toilet.
- Do not ignore the urge to have a bowel movement.
- Understand that normal bowel habits vary.
- Whenever a significant or prolonged change in
bowel habits occurs, check with a doctor.
7. Most people with mild
constipation do not need laxatives. However, doctors may recommend laxatives
for a limited time for people with chronic constipation.