Somewhere around week three on a GLP-1, a lot of people notice the same thing: the scale is finally moving, and the bathroom has gone quiet. Too quiet. Constipation is one of the most commonly reported side effects of semaglutide, tirzepatide, and the rest of the weight-loss injection family — and if you already had hemorrhoids, or were one bad week away from getting them, that constipation is not a minor footnote. It's the whole story.
GLP-1 medications work partly by slowing how fast your stomach empties. That's a feature, not a bug — it's a big part of why you feel full on half the food you used to eat. But the slowdown doesn't stop at your stomach. Transit through the rest of the gut slows too, and the longer stool sits in your colon, the more water your colon pulls back out of it. Slow transit plus dry stool equals hard stool.
Then the side effects stack. You're eating much less overall, which usually means less fiber without you ever deciding to eat less fiber. Some people drink less because they simply feel full or a little queasy. Less food, less fiber, less water, slower gut — every one of those pushes in the same direction. (This physician-reviewed explainer walks through the mechanics if you want the longer version.)
Hemorrhoids are cushions of blood vessels in and around your anal canal. Everybody has them. They become a problem when pressure makes them swell — and nothing delivers pressure quite like straining to pass a hard, dry stool. Push hard enough, often enough, and those vessels swell, bulge, and stay irritated. That's when you get the itching, burning, soreness, and the occasional streak of bright red blood on the paper.
So no, the injection doesn't cause hemorrhoids directly. The chain is: medication slows the gut, stools get hard, you strain, hemorrhoids flare. Break any link in that chain and you're in much better shape.
First, the thing not to do: don't stop or stretch out your doses on your own because of constipation. That's a conversation for your prescriber, who has options — slower dose escalation, a stool softener, or other adjustments. Constipation on these medications is common enough that no doctor will be surprised by the question.
What you can do on your own, starting today:
If the damage is done and you're sore right now, the goal is temporary relief while you fix the constipation upstream. A warm sitz bath — ten minutes, a couple of times a day — relaxes the area and eases that throbbing pressure; a dedicated soak like our Sitz Bath Soak makes it easy to be consistent. For the pain and swelling itself, Advanced Hemorrhoid Cream combines 5% lidocaine to numb the sting with phenylephrine to help temporarily shrink swollen tissue. And because dry toilet paper on an irritated area is its own small cruelty, swap it for gentle cleansing with our Hygienic Cleansing Lotion and pat — don't rub — dry.
To be clear about what those products do: they relieve hemorrhoid symptoms temporarily. They don't treat constipation and they don't change how your medication behaves. The medication conversation belongs with your prescriber.
Call your doctor if you're going several days without a bowel movement despite the fixes above, if you have severe belly pain or vomiting, or if constipation on your GLP-1 simply isn't improving — and see a doctor promptly for any rectal bleeding that's more than a light streak, is dark in color, or keeps happening. Bleeding is usually hemorrhoids, but "usually" is not a diagnosis, and it deserves a professional look.
The weight-loss results are real, and so is this side effect. Handle the constipation early and your hemorrhoids may never need to join the conversation.
This article is for informational purposes only and is not medical advice. Talk to your doctor or pharmacist about medication side effects and before starting any treatment.