Because the medication slows your gut, and appetite suppression usually crashes your fiber intake at the same time. Less food moving more slowly means less coming out. The fixes, in order: more water than you think you need, soluble fiber added gradually, magnesium, and daily movement. They work far better together than any one alone.
This is the number one thing women message me about once they've started a GLP-1 (whether yours is Ozempic, Wegovy, Mounjaro, or Zepbound), and it makes sense, because constipation is one of the most common digestive complaints on these medications. In perimenopause it's often worse, because estrogen decline slows the gut too, so midlife women get a double hit. The good news is it responds well to a handful of deliberate changes.
Why does a GLP-1 make me constipated?
Two things work against you at once. The medication slows how fast your stomach empties and how quickly everything moves through your gut. At the same time, appetite suppression means you eat much less, and high-fiber foods are usually the first to go. Less bulk moving more slowly, with less fiber, so things back up.
Two things are working against you at once. The medication slows how quickly your stomach empties and how fast everything moves through your gut, which is part of how it keeps you full. And appetite suppression means you're eating much less, with high-fiber foods usually the first to disappear from a smaller appetite. So you've got less bulk, moving more slowly, with less of the fiber that keeps things going. Things back up.
What actually helps GLP-1 constipation?
Water comes first, and more than feels necessary, because adding fiber without enough water makes things worse. Next, soluble fiber like psyllium, added gradually. Magnesium in the citrate form gently draws water into the bowel; ask your pharmacist how to time it with your other medications. Then daily movement, even just a walk.
Water comes first, and more than feels necessary. This matters especially because adding fiber without enough water makes constipation worse, not better. So hydration is the foundation everything else sits on.
Then soluble fiber, added gradually. Psyllium is the workhorse here, with strong evidence for regularity, but ramp it up slowly, because too much too fast causes bloating. Alongside it, keep whatever fiber-rich foods you can manage on a small appetite, vegetables and legumes especially.
Magnesium is a genuine ally. The citrate form gently draws water into the bowel, which is exactly what you want here, though it should be spaced away from certain medications, so ask your pharmacist how to time it with yours. Many women in midlife are low in magnesium anyway, so it tends to help on several fronts at once.
And movement, even just a daily walk. The gut responds to the body being in motion, and walking after meals does double duty by helping blood sugar too.
When should I talk to my prescriber about it?
If those changes aren't enough after a genuine effort, that's a real conversation to have with the person who prescribed your medication, not something to quietly endure. Persistent constipation is worth addressing, and there are options. You don't have to choose between the benefits of the medication and a gut that works.
If those changes aren't enough after a genuine effort, that's a real conversation to have with the person who prescribed your medication, not something to quietly endure. Persistent constipation is worth addressing, and there are options. You don't have to choose between the benefits of the medication and a gut that works.
This article is education, not medical advice, and does not replace guidance from your prescriber. Medication, dosing, and hormone therapy decisions belong with a qualified clinician who knows your history.