Posted On : December 26, 2011 Constipation is a prevalent problem in the adult U.S. population. This is not, however, an issue for most duodenal switch patients. Constipation is defined as having less than three bowel movements per week, and is considered severe if there is less than one bowel movement per week. The benchmark for normal bowel function is considered to be one bowel movement a day. Most of the time, the cause of constipation is considered idiopathic (no underlying origin identified). In these cases, the treatment is symptomatic.