Laxatives are products that help people empty their bowels, and there are many types. Stool softeners are laxatives that work by drawing water into the stool, making it softer and easier to pass. Stimulant laxatives stimulate the bowel muscles and help stool move faster.

All laxatives work in different ways, each with the intention of helping relieve constipation. Understanding the differences between laxatives and stool softeners may help a person decide which one to use.

Anyone dealing with regular constipation may also choose to make a few changes to their diet and lifestyle, which might help regulate their bowel movements.

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The term “laxative” refers to a wide range of substances, including stool softeners. A laxative is any medicine or supplement that helps the body have a bowel movement.

Each laxative works differently, and a doctor may suggest them as a first-line treatment alongside dietary and lifestyle advice to help relieve constipation.

Stool softeners are a type of laxative that works to gently lubricate the stool by adding a compound to it that absorbs water. Stool softeners are also called emollient laxatives.

There are many types of laxatives, because there are many different causes of constipation. Doctors may recommend different types of laxative depending on the cause of constipation or side effects of the medications.

Stool softeners are a type of laxative, but not all laxatives are stool softeners. Although some other laxatives also soften the stool, they have different methods of action.

Other types of laxative can include:

  • Osmotic laxatives: These draw water into the intestines from the surrounding tissues.
  • Bulk-forming laxatives: Often derived from plants, these laxatives help form a watery gel in the intestines that adds both body and lubrication to the stool.
  • Stimulant laxatives: These are fast-acting laxatives that can stimulate the intestines into having a bowel movement.
  • Saline laxatives: These magnesium-based laxatives pull water into the intestines.
  • Lubricant laxatives: These are oily laxatives that coat the intestines to help move stool through quicker.
  • Guanylate cyclase-C agonist laxatives: Certain drugs both increase water in the gastrointestinal tract and make the stool move through the colon faster.

A person should take only one type of laxative at a time. They should also consult a doctor before switching between them to avoid any interactions or complications.

In most cases, a doctor will know which type of laxative they should prescribe based on a person’s symptoms and what is causing them. The following list describes the uses, benefits, and risks of different forms of laxatives:

Stool softeners

Stool softeners are gentle medications with a relatively mild effect. They typically contain docusate sodium and docusate calcium as the active ingredients.

They help soften the stool, making it easier to pass. Over-the-counter (OTC) stool softeners are useful when a person experiences temporary, mild, or chronic constipation.

Doctors may prescribe stool softeners after major surgeries, such as heart surgery or hernia repair. If straining to have a bowel movement might be harmful during recovery, people can take stool softeners to avoid complications.

Osmotic laxatives

Osmotic laxatives work by drawing water into the intestines to help soften the stool and help it move. They usually contain polyethylene glycol and glycerin as their active ingredients. They may not be the best option for people experiencing constipation from dehydration.

Anyone using osmotic laxatives should also drink more water throughout the day. If used correctly, osmotic laxatives may be suitable for long-term use.

Fiber-based laxatives

Doctors may recommend a bulk-forming laxative containing soluble fiber if a person does not get a lot of fiber in their regular diet.

These laxatives often contain psyllium, methylcellulose, and calcium polycarbophil, which help form a gel in the stool that helps it hold more water and become larger, which stimulates the intestines.

Bulk-forming laxatives may be safer for long-term use than other options, as they have little risk of long-term side effects when taken correctly. However, they may take longer than other laxatives to work.

Doctors may also recommend fiber-based laxatives for people who have chronic, long-lasting constipation.

Saline laxatives

Like osmotic laxatives, saline laxatives pull water into the stool. Saline laxatives do this using mineral salts, such as magnesium citrate or magnesium oxide.

Saline laxatives are not suitable for everyone. For instance, people who take medication to lower their sodium levels or are taking other mineral-based drugs, such as medicines to reduce calcium in the kidneys, should avoid saline laxatives.

Saline laxatives are useful for short-term constipation. Using them for extended periods may lead to dehydration or cause an imbalance in other minerals.

If someone is unsure about the potential medication interactions that saline laxatives could cause, they should contact a healthcare professional for advice.

Lubricant laxatives

Doctors may recommend laxatives containing oils such as mineral oil for difficult, short-term constipation, but these are not suitable for regular use. The oils in these laxatives may stick to fat-soluble vitamins and make them impossible to digest.

Stimulant laxatives

Stimulant laxatives are a good option for fast relief from painful constipation. They often contain bisacodyl and sennosides as active ingredients.

The stimulating effect in these laxatives makes the stool move faster through the colon while increasing the liquid in the stool. Many popular OTC brand names contain stimulant laxatives.

Stimulant laxatives are not safe for regular use. Using them regularly may cause the body to become dependent on the laxative to have a bowel movement.

Guanylate cyclase-C agonist laxatives

Doctors may prescribe guanylate cyclase-C agonist laxatives in cases of chronic constipation that has no known cause.

These laxatives, along with lifestyle changes, may offer a solution for people who have chronic constipation. It is not advisable for young children to use them.

Stool softeners may be best when a person does not need immediate relief but is looking to regulate their bowel movements within the next few days.

The type of laxative a doctor recommends may also change based on how quickly a person needs relief. Individual result times may vary, but in general, the following applies:

  • Quick relief: Saline laxatives tend to work very fast.
  • Medium relief: Stimulant laxatives are fast-acting, but they still take some time to work.
  • Slow relief: Other laxatives, including bulk-forming fibers, stool softeners, and guanylate cyclase-C agonist laxatives, take longer to work.

The authors of a 2015 study looking at constipation in older adults observe the following:

  • Osmotic laxatives, including magnesium citrate and magnesium hydroxide, may produce a bowel movement in 30 minutes to 6 hours. Others may not take effect for 24–48 hours.
  • Stimulant laxatives, such as Dulcolax and Senna, may take 6–12 hours.
  • Stool softeners, such as Docusate, may take 24–48 hours.
  • Fiber-based laxatives, including Fibercon and Metamucil, can take 12–72 hours.

Doctors often recommend that people struggling with constipation make lifestyle changes to help ease their symptoms. Many people can find relief from constipation by drinking plenty of water and getting regular exercise.

A person can increase their daily fiber intake by including more fruits and vegetables in their diet. Fiber-rich foods that can help with constipation include:

  • Prunes: Prunes can help people stay regular. They contain both soluble and insoluble fiber, which may help absorb water and give body to the stool.
  • Apples: Apples are rich in pectin, a helpful soluble fiber. Try including apples as a snack between meals.
  • Pulses: Most beans, lentils, garbanzo beans, and peas are high in fiber, which helps promote good digestion and reduces constipation.

Learn more about natural stool softeners here.

All laxatives come with the risk of side effects. Some side effects are temporary, while others may be severe enough to warrant a change in medication.

Common side effects in all laxative types are:

  • stomach cramps
  • bloating or gas
  • nausea or vomiting
  • diarrhea

Some oral stool softeners may cause throat irritation when swallowed. Other side effects may vary based on the active ingredient in each laxative.

Misusing laxatives, such as taking them for extended periods, may cause severe and potentially dangerous symptoms.

Allergic reactions are also possible with all laxatives. Anyone who is having an allergic reaction or is unsure about their reaction should stop using the laxative and contact a doctor.

Importantly, laxatives may interact with other drugs a person is taking. People with constipation who take other drugs should seek guidance from a doctor or pharmacist before taking any laxative.

Occasional constipation is normal. Both stool softeners and other laxatives may provide temporary relief from symptoms, and the choice between them may depend on how quickly a person needs relief.

People may experience side effects or complications from taking certain laxatives. Anyone experiencing side effects that last more than a few days should contact a doctor to find out the cause.