15+ Natural Osmotic Laxative US. Natural laxatives are substances that help promote a bowel movement. Milk of magnesia, otherwise known as magnesium hydroxide, is a natural mineral.
They are used to treat and prevent constipation.
Osmotic laxatives may take one to two days to start working. Some laxatives are harsh and make you feel uncomfortable. If your poo is soft but you're still foods that are high in fibre can act as natural laxatives by making your poo softer and easier to pass. Four main classes of natural laxatives (bulk, osmotic and stimulating.