November 27, 2015
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Stool Color Changes (cont.)

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Drugs that change stool color

The most common drugs that change the color of stool are the drugs that turn the stool black that were previously discussed. Nevertheless, a large number of other drugs have been associated with changes in the color of stool to black or even other colors. Practically, the importance of this fact is that the any new drugs or dietary supplements need to be considered as the cause of any change in stool color.

Stool that floats

Most stool floats because it contains an excessive amount of gas. By itself it is normal and usually of no concern. Changes in diet can lead to stool that floats, but as an isolated symptom, no action needs to be taken, and often it resolves spontaneously. Stool does not float because of an increased amount of fat. (Fat in stool causes oil droplets in the toilet bowl.)

Any condition that causes increased amounts of gas to form in the intestines theoretically can lead to floating stool, especially in conditions in which there is malabsorption such as with lactose intolerance, celiac disease, cystic fibrosis, and short bowel syndrome.

Changes in the size and shape of stool

Each person has their own size, shape and consistency of stool. It is the change in stool pattern that matters more than the absolute size and shape of stool. Narrow stool, sometimes called pencil-thin, may occur occasionally and is of no concern. People with irritable bowel syndrome may develop thinner stools.

Nevertheless, a person with "normal" stools that has a new change in the diameter, length, width (caliber) of the bowel movement should consult his/her doctor. This may be a sign of a narrowed or scarred colon, perlhaps due to a tumor, but the doctor may want further information about accompanying symptoms or tests.

It is not unusual to have two or even three stools in a morning. The first stool will usually have a more solid form because it has been in the colon (where water is absorbed) the longest. The second stool will be looser, and if there is a third stool it will be loosest of all. Another change in stool form that often requires evaluation is the development of looser or firmer than normal stools. At one end of the spectrum is constipation or diarrhea, but even if the change does not reach these levels, consistent, milder changes in either direction need to be evaluated.

Medically Reviewed by a Doctor on 9/16/2015


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