Various brands are available ... stool softeners, and osmotic laxatives. Bulk-forming laxatives, which often are a form of fiber, add bulk and water to stools to make them easier to pass.

Lactulose operates like the other osmotic laxatives above, but it is available only by prescription. Brand names include Cephulac, Chronulac, Constilac, Cholac, Constulose, Duphalac, Enulose ...

Osmotic laxatives draw water into the bowel because they are hypertonic, essentially flushing the colon. Examples of osmotic laxatives include milk of magnesia (which also softens stools), sodium ...