Lactulose

Lactulose, an osmotic laxative, contains poorly absorbed ions or molecules that create a local osmotic gradient within the intestinal lumen. Fluid and electrolytes are drawn osmotically from the surrounding tissue into the colon, which creates pressure-stimulating peristalsis. Adverse effects of lactulose include electrolyte abnormalities, diarrhea, abdominal bloating, flatulence, and colic.