Chronic
constipation is defined as a symptom-based disorder based on the presence for at least 3 months in the last year of unsatisfactory defecation characterized by infrequent stools, difficult stool passage, or both. On the other hand, the presence of clinically important abdominal discomfort or
pain associated with
constipation defines
irritable bowel syndrome (IBS) with
constipation. Intake of dietary fibre and bulking agents (
psyllium) may be effective in alleviating chronic
constipation in patients without slow colonic transit or disordered
constipation. On the other hand, fibre may improve stool consistency in patients with IBS with
constipation, but it is considered to be not effective in improving
abdominal pain, distension or bloating. Probiotics may be effective in relieving
constipation; however, the effect of lactic acid bacteria ingestion may be dependent on the bacterial strain used and the population being studied.
Lactulose, which is a substrate for lactic acid bacteria (
prebiotic), is effective to treat patients with chronic
constipation.