How long does it take for stool softeners to work?

12 to 72 hours: Docusate (per pdr) helps moisten & soften hard, dry stools. It is not true laxative, but facilitates natural defecation, usually within 12 to 72 hours. This works best for occasional constipation, & assumes normal GI anatomy without inflammation, stenosis, extrinsic or instrinsic obstruction. Change in bowels is considered a "red flag", like weight loss or blood in stool, that if persists see doc.