Managing Constipation on GLP-1

When to Expect It

Constipation is one of the most common side effects of GLP-1 medications, affecting roughly 17% to 24% of patients. GLP-1 medications work in part by slowing the movement of food through the stomach and intestines. This slower transit, combined with reduced appetite and potentially lower fluid intake, can lead to less frequent or harder bowel movements.

• Constipation often begins within the first few weeks of starting the medication and may temporarily worsen with each dose increase.
• Symptoms are usually mild to moderate and tend to improve over time as your body adjusts to a stable dose.
• Proactive dietary and lifestyle strategies can significantly reduce symptoms.
• Low fiber intake, inadequate fluid intake, or a history of constipation may increase your risk.

‍

How to Manage It

Fiber: The Most Important Strategy

Fiber is the foundation of constipation management. Here is how to use it effectively:

‍Getting started:

• Increase fiber gradually — too much too fast causes gas and bloating
• Add one new high-fiber food at a time and increase by about 3–5 grams per week.
• Always increase your water intake alongside fiber. Fiber needs fluid to work properly — without enough water, it can actually make constipation worse.

How much to aim for:

• Aim for 25–35g of fiber per day from food sources first

‍Which types of fiber work best:

• Soluble fiber has the strongest evidence for relieving constipation. Good sources include psyllium (e.g., Metamucil), oat bran, barley, beans, and the flesh of fruits and vegetables.
• Insoluble fiber (wheat bran, whole grains, fruit and vegetable skins) adds bulk but may worsen bloating and discomfort in some people. If you notice increased bloating, focus more on soluble fiber sources.
• For the best results, choose fiber that is soluble and gel-forming — psyllium is the best-studied option.

A natural option worth trying:

• Try eating 2 green kiwifruits per day. Research shows this can increase bowel movements by 1–2 per week and improve stool consistency, with fewer side effects than fiber supplements.
• Prunes (about 100 grams or ~10 prunes per day) are another effective fruit-based option.

Hydration

Adequate water intake is essential for fiber to support bowel regularity. Without enough fluid, fiber can actually worsen constipation.

How much to drink:

• Aim for at least 64–80 ounces (8–10 cups) of fluid per day as a general target. A more personalized goal is roughly half your body weight (in pounds) in ounces of water per day.
• As a reference the National Academy of Medicine's adequate  daily water intake recommendations include 3.7 L/day (~125 oz) for men and 2.7 L/day (~91 oz) for women (total water from all sources including food).
• A simple check: pale yellow urine generally means you are well hydrated; dark yellow means you need to drink more.

Why this matters even more on GLP-1 medication:

• GLP-1 medications can reduce your sense of thirst. Research shows that people on these medications drink about 17% less fluid without realizing it. This means you cannot rely on feeling thirsty to remind you to drink.
• Set a schedule: drink water at regular intervals throughout the day rather than waiting until you feel thirsty. Try keeping a water bottle visible as a reminder.

A morning routine that helps:

• Having a drink (warm or cool) first thing in the morning or with meals can help trigger a natural reflex (called the gastrocolic reflex) that increases bowel activity. This is why many people find that a morning cup of coffee, tea, or warm water helps get things moving.

‍

High-Fiber Foods to Include

Movement & Behavioral Strategies

• Regular movement — even short daily walks (2–30 mins) — supports bowel regularity
• Try to establish a consistent bathroom routine,Try sitting on the toilet after meals (especially breakfast), when the gastrocolic reflex naturally stimulates bowel activity
• Don't delay or ignore the urge to go
• Elevating your feet on a small stool while on the toilet reduces straining
• Limit toilet time to 5 minutes per attempt — if no bowel movement, try again later
• Stress slows digestion further — brief relaxation practices may help

Over-the-Counter Options  (if lifestyle changes aren't enough)

• Osmotic laxatives (MiraLAX/PEG, milk of magnesia) — first-line OTC therapy; safe for ongoing use under provider guidance. Use magnesium products with caution if you have kidney problems
• Stool softeners (docusate/Colace) — may help with hard stools, but evidence is limited compared to other options
• Fiber supplements (psyllium/Metamucil) — add slowly, always with adequate water. Aim for 20–30g total daily fiber from food + supplements combined
• Stimulant laxatives (senna, bisacodyl) are effective for rescue or second-line use; discuss with your care team before using regularly
• Always discuss with your Onsera care team before using any laxative regularly

‍

Reach Out — Don't Wait It Out

• No bowel movement for 3 or more days despite dietary changes and adequate hydration
• Constipation is not improving after 1–2 weeks of consistent effort
• You have significant abdominal bloating or discomfort
• You're considering starting a laxative and want guidance on which is appropriate
• Constipation started or worsened significantly after a dose increase
• You notice a persistent change in the shape or caliber of your stools

Seek Urgent or Emergency Care If…

• Severe abdominal pain, cramping, or distension that is worsening
• No bowel movement for 5+ days with increasing discomfort or inability to pass gas. This combination may indicate a bowel obstruction
• Vomiting alongside inability to have a bowel movement — may indicate obstruction
• Blood in your stool
• Sudden severe pain that radiates to your back, especially if worsened by eating. This could be a symptom of pancreatitis.
• Fever combined with severe abdominal symptoms

‍

_{This guide is for educational purposes only. It does not take the place of personalized medical advice from your health care provider. Always consult your Onsera care team before making any changes to your medication or treatment plan}