Constipation: Definition, Causes & Impaction

An error occurred trying to load this video.

Try refreshing the page, or contact customer support.

Coming up next: Fecal Incontinence: Definition & Causes

You're on a roll. Keep up the good work!

Take Quiz Watch Next Lesson
Your next lesson will play in 10 seconds
  • 0:01 Intestinal Elimination
  • 0:31 Constipation
  • 1:35 Causes of Constipation
  • 4:31 Lesson Summary
Save Save Save

Want to watch this again later?

Log in or sign up to add this lesson to a Custom Course.

Log in or Sign up

Speed Speed
Lesson Transcript
Instructor: Artem Cheprasov

Artem has a doctor of veterinary medicine degree.

In this lesson, you're going to learn the general and specific definitions of constipation, some of the causes of constipation, as well as the definition of an impaction.

Intestinal Elimination

Poop. We don't like talking about it too much. It smells, and it doesn't look all that appetizing. But, the stuff we do find appetizing is what eventually becomes poop as it travels through the gastrointestinal (GI) tract, which is the digestive tract of the human body. Sometimes, everything goes in one end and comes out the other just fine. Other times, however, there are disturbances in intestinal elimination along the way. One of the things that can go wrong is constipation.


Constipation is a symptom, rather than a disease, which may be acute or chronic in nature, and results in a decreased frequency in the passage of stools and/or consists of stool that is hard and difficult to pass. When I say acute, it's not a 'cute' problem; acute mean it's of sudden onset and/or short duration. When I say chronic, I mean it is of long duration and/or recurrent in nature.

There is no one established definition of constipation, so what I gave you is just an example. Constipation is sometimes seen clinically simply as less than three bowel movements per week. However, newer criteria define it as at least two of the following symptoms in the last three months:

  • Less than three bowel movements per week
  • A hard stool or lumpy stool
  • Straining
  • A sensation that the anorectal region is blocked
  • A feeling that the person hasn't voided completely
  • The need to manually evacuate or help evacuate stool from the intestinal tract

Causes of Constipation

So, what could possibly cause all this trouble? What you eat and drink, or don't eat and drink, can play a humongous role in this problem.

Dehydration is a major cause of constipation as the stool dries out. Why? Well, in order to help move the stool along your digestive tract, the poop itself needs to remain a bit moist and slippery. But if the person is dehydrated, the body tries to conserve water for more critical needs like the function of the cardiovascular and nervous systems at the expense of the gut. This means water is reabsorbed from the bowel, the poop dries out, becomes hard, and the rest is history.

Another dietary factor that may lead to constipation is an inadequate amount of fiber. Some of the fiber we eat attracts water to the stool, keeping it nice and moist, and thus helping us defecate nice and easy. But it's not that easy, actually. I only wish that what we eat or drink was the only thing that affects the propensity to develop constipation. There are plenty of other causes of this problem.

One is diverticular disease, a general term that describes one of several disorders that cause the development of pouches in the wall of the colon, called diverticula. Diverticular disease causes decreased transit times through the colon, which can predispose a person to constipation. By this, I mean the time it takes for the poop to go from point A to point B, the transit time much like on highways, decreases. Things back up, get stuck like in a traffic jam, and voila! We have constipation.

To unlock this lesson you must be a Member.
Create your account

Register to view this lesson

Are you a student or a teacher?

Unlock Your Education

See for yourself why 30 million people use

Become a member and start learning now.
Become a Member  Back
What teachers are saying about
Try it risk-free for 30 days

Earning College Credit

Did you know… We have over 200 college courses that prepare you to earn credit by exam that is accepted by over 1,500 colleges and universities. You can test out of the first two years of college and save thousands off your degree. Anyone can earn credit-by-exam regardless of age or education level.

To learn more, visit our Earning Credit Page

Transferring credit to the school of your choice

Not sure what college you want to attend yet? has thousands of articles about every imaginable degree, area of study and career path that can help you find the school that's right for you.

Create an account to start this course today
Try it risk-free for 30 days!
Create an account