Who should have a colonoscopy?
Although it is preventable, colorectal cancer is still the
third-most common cancer diagnosed in the United States. In 2007,
142,672 people were diagnosed with it. Regular screening,
beginning at age 50 through to age 75, is the key to prevention.
Your doctor can advise you how often to get a colonoscopy.
If there is a history of colorectal cancer in your family, you
have a higher risk of developing it and should begin screening at
a younger age, and you may need to be tested more frequently.
What is a colonoscopy?
A colonoscopy enables the physician to examine the lining of the
colon (large intestine or large bowel) for abnormalities. The
colonoscope is a four-foot-long, flexible tube with a camera and
a source of light at its tip. While the patient is under
sedation, the tip of the colonoscope is inserted into the anus
and then is advanced slowly, under visual control, into the
rectum and through the colon.
Does it hurt?
No. The procedure, which can take as little as 15 minutes to an
hour or so, does not hurt. Patients are given medicine to sleep
through the test, so they don't feel anything. When air is pumped
into the colon (to keep it open, so that the doctor can get the
best and clearest picture), there may be some mild discomfort,
but it should not be painful.
What bowel preparation is needed for a
The colon has to be completely clean. In general, patients drink
a large volume of a special cleansing solution or undergo several
days of a clear liquid diet and laxatives. Patients have to
follow the instructions exactly as prescribed or the procedure
may not work properly and have to be repeated.
What should I expect during a colonoscopy?
Before a colonoscopy, the patient's heart rhythms and blood
pressure are monitored. Sedatives are usually given through an
intravenous line so that patients become sleepy and relaxed. If
needed, patients may receive additional doses of medication
during the procedure. During the procedure, patients lie on their
left side or back as the colonoscope is slowly advanced. Once the
tip of the colon is reached, the colonoscope is slowly withdrawn,
and the lining of the colon is carefully examined.
How long does it take?
A colonoscopy usually takes 15 to 60 minutes. If the entire
colon, for some reason, cannot be visualized, the physician may
decide to try a colonoscopy again at a later date with or without
a different bowel preparation or may decide to order an X-ray or
CT of the colon.
What should I expect after the colonoscopy?
Patients are kept under observation for an hour or two after
their colonoscopy, until the effects of medications wear off. If
patients have been given sedatives before or during colonoscopy,
they can't drive, even if they feel alert.
When will I get the results?
After the procedure, your doctor will discuss his or her
findings. However, a definitive diagnosis may take several days
longer, as a microscopic analysis of any biopsy specimens may be
What if an abnormality is found?
If your doctor thinks an area of the bowel needs to be evaluated
in greater detail, a biopsy will be taken and analyzed. If polyps
are found, they are generally removed if it is safe to do so.
Generally, these procedures are not painful.