Why It Happens
GLP-1 medications slow down your entire digestive system—not just your stomach, but your intestines too. This is actually part of how they work (slower digestion = feeling full longer). But slower bowel transit means constipation for many people.
Add to that: you're eating less. Less food in = less stool to move through. And if you're not drinking enough water, everything slows down further.
Constipation on GLP-1 is extremely common. It's uncomfortable, but manageable.
Solutions That Work
💧 Hydration First
Dehydration is a major constipation driver. With GLP-1 reducing your appetite, you may also be drinking less without realizing it.
Target: At least 64 oz of water daily. More if you're active or in a hot climate. Set reminders if needed.
🥗 Fiber (The Right Way)
Fiber adds bulk and helps move things along. But there's a catch: adding fiber without enough water makes constipation worse.
Good sources: Vegetables, fruits, beans, whole grains, psyllium husk (Metamucil)
Start slow: Increase fiber gradually. A sudden spike can cause bloating and make you more uncomfortable.
💊 Magnesium Citrate
This is the go-to supplement for many GLP-1 users. Magnesium citrate draws water into the intestines and has a gentle laxative effect.
Typical dose: 200-400mg at bedtime. Start low and adjust based on results.
Note: Magnesium citrate is different from other forms (like magnesium glycinate for sleep). The citrate form specifically helps with bowel movements.
🏃 Movement
Physical activity stimulates intestinal contractions. Even a 20-minute walk can help get things moving.
Try this: A morning walk, especially after coffee or breakfast, can trigger a bowel movement.
☕ Coffee (If You Tolerate It)
Coffee stimulates the gastrocolic reflex—a fancy term for "makes you need to poop." This effect is independent of caffeine; even decaf works for some people.
Timing: Morning coffee on an empty or lightly-filled stomach tends to be most effective.
💊 OTC Options When Needed
If lifestyle changes aren't enough, over-the-counter options can help:
• Miralax (polyethylene glycol): Gentle osmotic laxative. Works by drawing water into stool. Safe for regular use.
• Colace (docusate): Stool softener. Makes stool easier to pass.
• Dulcolax: Stimulant laxative. Use sparingly—your body can become dependent.
What NOT to Do
- Don't ignore it. Chronic constipation can lead to hemorrhoids, anal fissures, and impaction.
- Don't rely on stimulant laxatives long-term. They can reduce your colon's natural ability to contract.
- Don't decrease fiber if you're already low. You need fiber, just pair it with water.
When to Call Your Provider
Contact your healthcare provider if you experience:
- No bowel movement for 5+ days
- Severe abdominal pain or cramping
- Blood in stool
- Vomiting with constipation
- Unexplained weight loss beyond expected GLP-1 effects
The bottom line: Hydration + fiber + magnesium citrate solves constipation for most GLP-1 users. Start with these before reaching for laxatives.
Prevention Protocol
Many users find that staying ahead of constipation works better than treating it after the fact:
- Drink water consistently throughout the day
- Take 200-400mg magnesium citrate daily
- Include vegetables and fiber at each meal
- Move your body daily (even just walking)
- Don't wait until you're severely backed up to act
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