Twenty nine female patients (mean age of 39 year: range 19-64) with chronic constipation received 2 weeks of lubiprostone (24 mcg b.i.d., P.O.). Stool consistency based on Bristol stool scale and the frequency of bowel movements were recorded. Gastric emptying time (GET), small bowel transit time (SBTT), colon transit time (CTT), combined small & large bowel transit time (SLBTT) and whole gut transit time (WGT) were measured using wireless motility capsule. Small bacterial overgrowth (SIBO) status was assessed by the lactulose breath test.