Stimulants cause rhythmic muscular contractions in the small or large intestine. These agents can lead to dependency and can damage the bowel with prolonged daily use. Stool softeners , or wetting agents, provide moisture to the stool and prevent excessive dehydration. These laxatives often are recommended after childbirth or surgery. Lubricants grease the stool and make it slip through the intestine more easily.
Mineral oil is the most commonly used lubricant.
Osmotics are salts or carbohydrates that cause water to remain in the intestine for easier movement of stool. Laxatives in the group include milk of magnesia, citrate of magnesia, lactulose, and Epsom salts.