What causes constipation?
Theoretically, constipation can be caused by the slow passage of digesting food through any part of the intestine. More than 95% of the time, however, the slowing occurs in the colon.
Medications
A frequently over-looked cause of constipation is medications. The most common offending medications include:
Narcotic pain medications such as codeine (for example, Tylenol #3), oxycodone [...]