Which Type of Laxative Is Considered Best to Use? A Guide to Constipation Relief

October 10, 2025 •

4 min read

According to the National Institute of Diabetes and Digestive and Kidney Diseases, constipation affects a significant portion of the population. When dietary and lifestyle adjustments are not enough, understanding which type of laxative is considered best to use is crucial for finding effective and safe relief. The best choice depends on the specific cause and severity of your symptoms.

Quick Summary

Different types of laxatives offer varied solutions for constipation, with bulk-forming options considered the safest for daily use, while osmotic and stimulant versions provide faster, targeted relief. The most suitable choice depends on the individual's needs.

Key Points

Gentle Start: Bulk-forming laxatives are the safest and gentlest option, mimicking the body's natural processes, but require ample fluids and take a few days to work.
Daily Use: Osmotic laxatives like MiraLAX are effective for both occasional and chronic constipation, drawing water into the colon with minimal side effects, and are a frequent first-choice recommendation.
Fast Relief: Stimulant laxatives provide quick relief for occasional constipation by promoting intestinal muscle contractions, but are not recommended for long-term use due to the risk of dependency and cramping.
Preventing Strain: Stool softeners are best suited for situations where straining should be avoided, such as after surgery, but are not a good long-term solution for chronic constipation.
When to See a Doctor: For chronic or severe constipation, or if you experience alarm symptoms like weight loss or rectal bleeding, consult a healthcare provider to explore potential underlying causes and discuss prescription options.

The Foundation: Lifestyle Changes First

Before reaching for medication, it is important to address lifestyle factors that contribute to constipation. The foundation of healthy bowel function relies on adequate fiber intake, sufficient hydration, and regular exercise. Diet should include high-fiber foods such as fruits, vegetables, and whole grains. Drinking plenty of water daily is crucial, as is engaging in regular physical activity, which helps stimulate intestinal muscle contractions. If these measures do not provide relief, over-the-counter (OTC) laxatives may be necessary.

Bulk-Forming Laxatives: The Gentle, Natural Approach

Bulk-forming laxatives, also known as fiber supplements, are widely considered the safest and gentlest option for treating constipation. They work by absorbing water in the intestines to form a bulky, soft stool, which helps trigger the natural bowel contraction process. Examples include psyllium (Metamucil) and methylcellulose (Citrucel).

Who they are for: Mild to moderate, non-chronic constipation, or as a long-term fiber supplement.
How long they take to work: They are not fast-acting and typically take anywhere from 12 hours to three days to produce a bowel movement.
Key consideration: It is vital to drink plenty of fluids when taking bulk-forming laxatives to prevent the fiber from causing an intestinal blockage. Mild side effects like gas and bloating may occur as your body adjusts.

Osmotic Laxatives: Drawing Water for Softer Stools

Osmotic laxatives work by drawing water from the rest of the body into the bowel, softening the stool and promoting easier passage. A popular and well-regarded example is polyethylene glycol (PEG 3350), commonly sold as MiraLAX. Other osmotic laxatives include magnesium-based products like Milk of Magnesia and magnesium citrate.

Who they are for: Often recommended for both occasional and chronic constipation, as they are effective and generally cause fewer side effects than stimulants.
How long they take to work: Oral osmotic laxatives like MiraLAX typically take one to four days to produce results. Faster-acting osmotic laxatives, like some saline products, can work in under an hour but should be used with caution.
Key consideration: People with kidney disease should use magnesium-based osmotic laxatives only with a doctor's guidance due to the risk of magnesium accumulation. Side effects can include bloating, cramping, and gas.

Stimulant Laxatives: For Faster, Short-Term Relief

Stimulant laxatives work by triggering rhythmic contractions in the intestinal muscles, which helps push stool through the bowel more quickly. Examples include senna (Senokot) and bisacodyl (Dulcolax).

Who they are for: Patients with occasional constipation requiring quick relief or those whose bowels are sluggish. They are generally not recommended for long-term use.
How long they take to work: Orally administered stimulant laxatives typically work within 6 to 12 hours. Suppositories work much faster, often within 15 to 60 minutes.
Key consideration: Extended or frequent use can lead to dependency, where the bowels begin to lose their natural ability to contract. Side effects like cramping, abdominal pain, and diarrhea are common.

Stool Softeners: Increasing Moisture in Hard Stool

Stool softeners, or emollient laxatives, work by adding moisture and fat to the stool to make it easier to pass. A common example is docusate sodium (Colace).

Who they are for: They are often recommended for short-term use, such as after surgery or childbirth, to prevent straining.
How long they take to work: Stool softeners take a bit longer to be effective, typically between one and three days.
Key consideration: Research suggests stool softeners may not be effective for chronic constipation. They are a milder option and may not be powerful enough for more severe cases.

Comparing Types of Laxatives: Finding the Right Match


Laxative Type	Mechanism	Onset of Action	Best For	Considerations/Side Effects
Bulk-Forming (e.g., Metamucil, Citrucel)	Adds fiber and absorbs water to increase stool bulk.	12 hours to 3 days	Mild, occasional constipation; long-term fiber supplementation.	Requires ample fluids; may cause bloating and gas.
Osmotic (e.g., MiraLAX, Milk of Magnesia)	Draws water into the colon to soften stool.	1 to 4 days (oral PEG); 30 min to 6 hrs (saline).	Occasional or chronic constipation.	Can cause bloating, cramping, and gas. Magnesium-based options require caution with kidney issues.
Stimulant (e.g., Senokot, Dulcolax)	Stimulates intestinal muscle contractions.	6 to 12 hours (oral); 15 to 60 min (suppository).	Occasional, quick relief for stubborn constipation.	Not for long-term use; risk of dependency and cramping.
Stool Softeners (e.g., Colace)	Adds moisture to soften hard, dry stool.	1 to 3 days	Preventing straining after surgery or childbirth.	Less effective for chronic constipation.

When Over-the-Counter Options Aren't Enough

If lifestyle changes and OTC options don't work, especially for chronic or severe constipation, a healthcare provider should be consulted. They can determine the underlying cause and recommend other options, including prescription medications. These may include secretagogues like Linzess or Amitiza, or agents specifically for opioid-induced constipation like Movantik. Your doctor may also recommend other tests to rule out serious conditions if there are alarm symptoms such as unintentional weight loss or rectal bleeding.

Conclusion: Tailoring Your Approach to Constipation Relief

There is no single best laxative for everyone, and the right choice depends on your specific symptoms, health status, and desired speed of relief. Bulk-forming and osmotic laxatives are generally the safest and most recommended starting points, particularly for regular or chronic issues, while stimulants are best reserved for short-term, occasional use. Consulting a healthcare provider is the most reliable way to find the optimal strategy for managing your constipation, ensuring you receive personalized advice tailored to your needs. Always prioritize lifestyle changes first and follow product directions carefully to avoid potential side effects and complications like dependency or electrolyte imbalance.

For additional information on managing chronic constipation, consult authoritative sources such as the National Institutes of Health. https://pmc.ncbi.nlm.nih.gov/articles/PMC8191753/

Frequently Asked Questions

For chronic constipation, osmotic laxatives like polyethylene glycol (MiraLAX) and bulk-forming laxatives like psyllium (Metamucil) are often considered the best options. They work gently and can be used long-term under a doctor's supervision. Stimulants are generally avoided for chronic use due to the risk of dependency.

For the fastest possible relief, stimulant laxatives, particularly in suppository form (e.g., Dulcolax suppositories), are the best choice. They typically work within 15 to 60 minutes. Oral stimulant laxatives, like senna or bisacodyl, work within 6 to 12 hours.

Yes, for many people, increasing dietary fiber through fruits, vegetables, and whole grains, along with drinking more fluids and getting regular exercise, can resolve constipation without medication. Prunes and prune juice are also well-known for their natural laxative effects.

Bulk-forming laxatives are generally considered the safest for regular, daily use. As fiber supplements, they add bulk and moisture to the stool. It is crucial to drink plenty of water to prevent blockages.

It is possible to combine some laxative types, such as a bulk-forming and an osmotic laxative, but it's best to consult a healthcare provider or pharmacist first. The combination of a bulk-forming and a stimulant can also be effective. Overusing or combining improperly can cause side effects like cramping or dehydration.

Stimulant laxatives should be avoided for long-term or routine use, as the bowel can become dependent on them to function. They may also cause significant cramping and discomfort. They are typically best reserved for occasional or severe constipation.

Stool softeners, such as docusate sodium (Colace), are often recommended after surgery to prevent straining during bowel movements. They work by making stools softer and easier to pass.