What Supplements Should I Take for Constipation on GLP-1?

December 14, 2025 •

4 min read

GLP-1 medications, used for weight management and diabetes, are known to slow gastric emptying, which can cause constipation in up to 20% of users. This digestive slowdown can be managed effectively with the right dietary and supplemental strategies, but it is important to choose options that work well with your medication.

Quick Summary

This guide provides detailed, expert-backed information on which supplements, including fiber, magnesium, and probiotics, can help relieve constipation caused by GLP-1 medications. It offers practical advice on types and safety considerations.

Key Points

Start with Fiber and Hydration: Before any supplements, increase fluid intake and eat more fiber-rich foods like fruits, vegetables, and whole grains.
Choose Gentle Bulk-Forming Fiber: Psyllium husk (Metamucil) is a reliable first choice to add bulk and softness to stool, but always drink plenty of water with it.
Use Magnesium as an Osmotic Laxative: Magnesium oxide or magnesium citrate can draw water into the bowels for effective, gentle relief. Avoid if you have kidney problems.
Opt for PEG 3350 for Gentle Daily Use: Polyethylene glycol (MiraLAX) is another effective osmotic option, considered gentle and safe for long-term management of GLP-1 constipation.
Reserve Stimulant Laxatives for Short-Term Use: Stimulants like senna can provide quick relief but are not for long-term use due to dependency risk.
Combine with Lifestyle Changes: Regular exercise and maintaining a consistent toilet routine are crucial for supporting digestive motility.
Consult a Professional: Always talk to your healthcare provider before starting any new supplement regimen, especially when on GLP-1 medication.

Understanding GLP-1 Induced Constipation

Glucagon-like peptide-1 (GLP-1) receptor agonists, such as semaglutide (Ozempic, Wegovy, Rybelsus) and tirzepatide (Mounjaro, Zepbound), slow the rate at which food moves through your gastrointestinal tract. This is a key mechanism for managing appetite and blood sugar, but it can also lead to common side effects like nausea and constipation. When food and waste linger longer in the colon, the body has more time to absorb water, resulting in harder, drier stools that are difficult to pass. This makes selecting the right supplements and adjusting your routine essential for comfort and continued success with your medication.

The Foundational Role of Hydration and Dietary Fiber

Before reaching for supplements, optimizing your water and fiber intake from whole foods is the first and most crucial step. Adequate fluid is necessary to keep stools soft, and fiber provides the bulk needed to move waste along. Aim for a daily fiber intake within recommended guidelines, and remember that when increasing fiber, you must also increase your water intake to avoid making constipation worse.

Some excellent food sources of fiber include:

Fruits: Berries, pears, and apples (with skin)
Vegetables: Leafy greens, broccoli, carrots, and legumes
Whole Grains: Oats, whole-wheat bread, and brown rice
Seeds: Chia seeds and flaxseeds, which can be added to smoothies or yogurt

Effective Supplements for GLP-1 Constipation

When diet alone isn't enough, several over-the-counter supplements can provide gentle relief. It is always wise to consult a healthcare provider before starting any new supplement, especially if you have underlying health conditions or are on other medications.

Bulk-Forming Fiber Supplements

These work by absorbing water to create soft, bulky stool that is easier to pass. They are often a first-line treatment for GLP-1 constipation.

Psyllium Husk: Found in products like Metamucil, psyllium is a soluble fiber that forms a gel in the intestines. Some research indicates that specific amounts can be effective. Start with a low amount and increase gradually to minimize gas and bloating.
Methylcellulose: The active ingredient in Citrucel, this fiber also adds bulk to stool but is less likely to cause gas than psyllium.

Osmotic Laxatives

Osmotic laxatives pull water into the colon to soften the stool and make it easier to pass. This is a gentle yet effective approach, suitable for daily or as-needed use.

Magnesium Oxide/Citrate: Magnesium is a proven osmotic agent for constipation relief. Magnesium citrate is often used for rapid relief, while magnesium oxide can promote daily regularity without dependency. Caution is advised for those with kidney disease, as magnesium can accumulate.
Polyethylene Glycol (PEG 3350): Found in MiraLAX, PEG 3350 is a non-absorbed solution that draws water into the colon. It is tasteless and considered a gentle and safe option for managing GLP-1 constipation.

Stool Softeners

For mild cases or to prevent hard, dry stools, a stool softener may be sufficient. They work by allowing water and fat to penetrate the stool, but are less effective for moving things along.

Docusate Sodium: The active ingredient in Colace, this is a very gentle option that can be used adjunctively with other treatments.

Gut Health-Supporting Supplements

For long-term digestive health, consider supporting your gut microbiome, which can be affected by changes in digestion while on GLP-1s.

Probiotics: Some evidence suggests that probiotics, particularly strains like Bifidobacterium lactis, can improve stool frequency and consistency. Probiotic supplements can be helpful, and fermented foods like yogurt and kefir are also good sources.
Digestive Enzymes: These can help your body break down food more efficiently, which is important if you experience heaviness or bloating with meals on a GLP-1.

Comparison of Constipation Supplements


Supplement Type	Mechanism	Speed of Relief	Best For	Considerations
Bulk-Forming Fiber (Psyllium)	Absorbs water to add bulk to stool.	Gradual (typically takes time to see effects).	Long-term prevention and management.	Must be taken with plenty of water. May cause gas/bloating initially.
Osmotic Laxatives (Magnesium, PEG 3350)	Draws water into the bowel to soften stool.	Moderate (Onset varies depending on the specific osmotic laxative used).	Effective, gentle relief for harder stools.	Magnesium requires caution with kidney issues.
Stool Softeners (Docusate Sodium)	Adds moisture to stool.	Moderate (typically takes time to see effects).	Mild cases or prevention of straining.	Not effective for severe, established constipation.
Stimulant Laxatives (Senna, Bisacodyl)	Causes intestinal muscle contractions.	Fast (Onset varies depending on the specific stimulant laxative).	Occasional, acute relief only.	Not for long-term use due to risk of dependency and cramping.

Holistic Management Approach

Managing constipation on GLP-1s goes beyond just supplements. Incorporating these holistic strategies can significantly improve bowel regularity:

Regular Exercise: Physical activity helps stimulate intestinal motility. Even a daily walk can make a difference.
Maintain a Routine: Your bowels thrive on consistency. Setting aside a regular time each day to use the toilet can train your body to have more regular movements.
Listen to Your Body: Never ignore the urge to have a bowel movement, as this can worsen constipation.
Consider Position: Using a small footstool to elevate your knees above your hips can help with easier passage by optimizing colon alignment.

Conclusion

GLP-1-induced constipation is a common but manageable side effect. By prioritizing hydration and fiber-rich whole foods, and strategically using supplements like psyllium husk, magnesium oxide, or PEG 3350 when needed, you can maintain digestive regularity. While supplements offer effective solutions, they should always be used in conjunction with lifestyle adjustments and under the guidance of a healthcare professional. For chronic or severe symptoms, or if simple remedies prove ineffective after a week, consult your doctor to explore further options and rule out other underlying issues. For additional support, consider consulting a gut-health dietitian for a personalized plan to manage your symptoms.

Frequently Asked Questions

Yes, psyllium husk supplements like Metamucil are often recommended as a first-line treatment for GLP-1 constipation. It is a bulk-forming fiber that adds mass and softness to stool. Be sure to drink plenty of water to prevent it from worsening your constipation.

For most people with healthy kidney function, certain forms of magnesium, like magnesium oxide, are a safe and gentle option for daily constipation management. However, those with kidney disease should avoid magnesium supplements and consult their doctor.

For fast, temporary relief, osmotic laxatives like magnesium citrate or polyethylene glycol (MiraLAX) can work effectively. Stimulant laxatives like senna are faster but should only be used sparingly for acute relief due to the risk of dependency.

Adding fiber supplements can cause temporary bloating and gas, especially when you first start. To minimize this, begin with a small amount and increase it gradually over time. Ensure you are also drinking plenty of water, which helps the fiber move through your system smoothly.

Probiotics can help support overall gut health and may improve stool frequency and consistency over time by balancing your gut bacteria. While not a rapid fix, they can be a useful long-term strategy. Fermented foods are also a good source.

Yes, some supplements should be avoided or used with caution. High amounts of Vitamin C and zinc can worsen GI symptoms like diarrhea, and certain herbal supplements like berberine or high-calorie meal replacements can interfere with the medication's effectiveness. Always consult your healthcare provider before starting any new supplement.

Hydration is extremely important, especially when taking bulk-forming fiber supplements like psyllium husk. Without enough water, the fiber can solidify and worsen constipation. Aim for adequate daily fluid intake, particularly alongside your fiber intake.