What is Atonic Colon?

Lazy Colon - One Reason Why Constipation is Serious

Hand reaching for toilet paper
What is atonic or "lazy" colon and what are the symptoms, causes, and treatments?. Photo by Brook Rieman/Moment/Getty Images

Atonic colon (pronounced ay-TAW-nik KOH-lun) occurs when there is a lack of normal muscle tone or strength in the colon. Also, known as lazy colon or colon stasis, it may result in chronic constipation. When your intestines are backed up, as in constipation, it slows the rate in which your stomach can empty, which in turn may cause heartburn.

Atonic colon is essentially a "vicious circle" phenomena.

Constipation can lead to reduced bowel activity, which in turn can lead to a worsening of constipation, and so on.

Common Misspellings: Atomic colon

Also called: Atonic bowel, lazy colon, colon stasis

Causes of Atonic Colon

While the cause of atonic colon is often unknown, chronic laxative use can be to blame. A relatively rare cause is Hirschsprung's disease, which is a blockage in the large intestine that has been brought about by poor muscle movement in the bowels. But Hirschsprung's disease isn't something you can develop or catch, it is congenital condition, which means that it is present from birth. It is also known as congenital megacolon.

With a megacolon, the bowel becomes extremely dillated and atonic (not moving) with a large amount of stool "just sitting there."

The Science Behind Atonic Colon

In many ways, atonic colon is an example of classical conditioning. Simplistically, the colon begins to "give up" when a stimulus does not result in evacuation of the bowel and stops responding to signals.

This can be similar to a parent, who after hearing a child ask for something a few dozen times, begins to "not hear" the requests. In contrast, in conditions such as Hirschsprung's disease, the ganglia, or collection of nerves controlling this function are absent.

The Link to Laxatives

Atonic colon is often seen as a side effect to laxative addiction.

Laxatives work by stimulating the bowel muscles with irritants. However, when they are used repeatedly, the muscles build up a tolerance and larger quantities of the irritants are needed to get the same effect. This causes low muscle tone, which results in an atonic colon. When defecation can only occur with the use of a laxative, this is laxative addiction. 

Symptoms of Atonic Colon

Besides constipation, you may also experience stomach pains, bloating, nausea, vomiting, and fever. Whether you are experiencing any, some, or all of these symptoms, make an appointment to see your physician.

Talking to Your Doctor About Constipation

Discussing your bathroom habits can be almost as uncomfortable as the constipation that you are experiencing. But when it is time to speak to your doctor, it is time to be a partner in your care. Meaning, don't hide anything, especially if you have been using laxative for an extended period of time. Also, try to do some pre-appointment work.

When trying to pinpoint the cause of your constipation, there are a few questions that your doctor may ask you.

Be prepared to answer the following:

  • How often do you have a bowel movement?
  • Have there been any changes in your bowel habits (i.e, frequency, ease)?
  • Have you noticed any change in the bulk of your stools?
  • Do you feel that you have emptied your bowels entirely after you go to the toilet?

​And since constipation can be caused by other things besides an atonic colon, don't be surprised if your doctor wants to talk about your mood — depression can trigger constipation; your sleeping patterns — insomnia can affect bowel movements; your energy levels — if your thyroid isn't working properly (hypothyroidism), neither will your bowels; and your exercise habits — if you lead a sedentary lifestyle, this can also affect your output.

​Possible Treatments for Atonic Colon

If laxatives are the cause to your lack of bowel muscle tone, they will not be used to combat the chronic constipation you are experiencing. Instead, your doctor may use enemas, or suggest bowel retraining. Another treatment that is sometimes used for chronic constipation, especially when the cause is closely related to the digestive system, is biofeedback.

Tips for Coping with Constipation to Help Prevent Atonic Colon

Understanding a bit about the science between bowel emptying can help explain what measures can help prevent the constipation that can lead to atonic colon.

  • Listen to nature. The bowel is most active in the morning and following meals. Passing stool is easiest when your efforts combine with this physiology.
  • Make sure you have enough fiber in your diet (but not too much which can lead to pain, bloating, and other problems.) Fiber increases the water content of stool so that it moves easier through the gut. Fiber also increases the weight of stool, assisting in the gravity part of the equation.
  • Work with your doctor to retrain your bowel habits.
  • Keep a defecation journal. Sometimes patterns become much clearer when they are spelled out in writing.

Sources:

Kasper, Dennis L., et al. Harrison's principles of internal medicine. New York: McGraw Hill Education, 2015. Print.

Sergi, M., Caluseriu, O., McColl, H., and D. Eisenstat. Hirschsprung's disease: clinical dysmorphology, genes, micro-RNAs, and future perspectives. Pediatric Research. 2016 Nov 2. (Epub ahead of print).

Continue Reading