Osmotic laxatives

These laxatives work by pulling water into the colon, which softens the stool and makes it easier to pass.

Laxatives such as Epsom salt work in a way similar to bulk-forming laxatives in that they attract water to the colon to soften and swell the stool. Osmotic agents, however, draw water not only from the colon itself, but also from surrounding tissue and blood vessels. As a result, it is very important that people using these types of laxatives drink plenty of liquids (water) to balance out any loss of fluid.

Because some of the salts contained in these products are absorbed by the body, use by people with high blood pressure, weak heart muscles or kidney disease may not be advisable. It is recommended that people with such conditions, consult their physicians.

Sugar and alcohol-based laxatives such as lactulose and lactitol ferment in the intestine, forming acids that stimulate the bowel muscles. They can take three days to work the first time they are used and may be associated with complaints of painful intestinal gas.

Bulking agents | Plat-derived purgatives | Synthetic stimulants