Constipation is a common symptom. It affects virtually everyone at some point in their life. Occasional constipation may result from changes in diet or from inactivity and will generally respond to simple lifestyle measures. However, constipation that is chronic (constant or long-lasting) or recurrent may indicate the need to see a doctor for evaluation and treatment.

What Is Constipation?

There is no single, generally accepted definition of constipation. The term “constipation” can refer to infrequent evacuation (bowel movement), difficult evacuation, incomplete evacuation, or evacuation of small or hard stools. Among these symptoms, only stool frequency is easily quantifiable and is usually defined as fewer than three bowel movements per week. Physicians often associate constipation with reduced stool frequency.

Patients, however, typically define constipation as the occurrence of one of more symptoms of infrequent stools or difficult stool passage including hard or lumpy stools, straining, a feeling of incomplete evacuation, excessive time spent on the toilet, or the need to manually facilitate stool passage.

Researchers frequently use the Rome III criteria to define constipation.

Given the various possible definitions of constipation, it is hardly surprising that the reported prevalence of constipation is quite variable. Studies from North America show prevalence rates of 2–27%, with most estimates ranging from 12–19%. Estimates based upon symptom self-reporting are significantly higher than those using Rome criteria.

Risk factors for the development of constipation include increasing age, female gender, nonwhite race, and lower socioeconomic status.

Rome III Diagnostic Criteria for Functional Constipation*

1. Must include two or more of the following:

     a. Straining during at least 25% of defecations





     f. Fewer than three defecations per week

2. Loose stools are rarely present without the use of laxatives

3. Insufficient criteria for irritable bowel syndrome


– Drossman DA et al, Rome III, 2006




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