Chronic constipation is defined as infrequent bowel movements or straining with defecation lasting for longer than a few weeks. In adults, this can be idiopathic, due to pelvic floor dysfunction or slow colonic transit, or secondary, caused by numerous medical conditions (eg, diabetes mellitus [type I, type II], Parkinson disease, pregnancy, systemic sclerosis, hypokalemia, hypothyroidism). Constipation can also be due to a medication.

Constipation can be asymptomatic or can cause pain with defecation, chronic abdominal pain (often left lower quadrant), abdominal distension, and the sensation of incomplete fecal voiding. Fewer than 3 bowel movements per week can be categorized as constipation, although bowel frequency is an unreliable marker as a patient's baseline frequency varies widely among the general population.

A thorough history can help elucidate any implicated medications or systemic disorders that can cause constipation.