- Common: in the STEP 1–3 trials, 24.2% of adults on semaglutide 2.4 mg (Wegovy) reported constipation vs 11.1% on placebo. On tirzepatide (Zepbound), it was 11–17% vs 5%.1,5
- It lasts longer than other stomach side effects: a median of 47 days per episode on semaglutide, vs 8 days for nausea.1
- Guidance puts fluids, fiber from food and activity first. Severe belly pain, vomiting, a swollen belly or not passing stool or gas needs prompt medical care.3,4,6
How common is constipation on Ozempic, Wegovy, Zepbound and Mounjaro?
The best numbers come from the placebo-controlled trials summarized in each US label. Placebo rates matter here, because constipation is also common with weight loss and in people with obesity in general.4
| Medicine and population | Constipation on drug | On placebo |
|---|---|---|
| Semaglutide 2.4 mg (Wegovy), adults with overweight or obesity, STEP 1–3, 68 weeks | 24% | 11% |
| Semaglutide 7.2 mg (Wegovy), adults with obesity | 20% (19% on 2.4 mg) | 8% |
| Tirzepatide 5 / 10 / 15 mg (Zepbound), adults with overweight or obesity, SURMOUNT-1 and -2, 72 weeks | 17% / 14% / 11% | 5% |
| Semaglutide 0.5 / 1 mg (Ozempic), adults with type 2 diabetes | 5% / 3.1% | 1.5% |
| Tirzepatide 5 / 10 / 15 mg (Mounjaro), adults with type 2 diabetes | 6% / 6% / 7% | 1% |
Two things stand out. Rates are higher at the weight-loss doses than at the diabetes doses. And on Zepbound, constipation was reported less often at the highest dose than at the lowest one. In the Mounjaro label's large heart outcomes trial of adults with type 2 diabetes and heart disease, 13% reported constipation.5
How long does GLP-1 constipation last?
A pooled analysis of the STEP 1, 2 and 3 trials followed 2,117 adults on semaglutide 2.4 mg and 1,262 on placebo for 68 weeks. It tracked when each stomach side effect started and stopped.1
Nausea, diarrhea and vomiting came and went within days. Constipation was different: episodes lasted weeks, and the share of people affected rose early, then plateaued at about week 10. The authors suggest this may reflect how GLP-1 medicines slow movement through the gut.1
It does tend to ease. In the STEP 4 trial, people who had already tolerated 20 weeks of semaglutide and stayed on it saw the share with constipation fall gradually over the rest of the trial.1 A 2022 expert consensus notes that constipation can start in the first 16 weeks of treatment, particularly in the first 28 days.3 For tirzepatide, an analysis of SURMOUNT-1 to -4 found stomach side effects mostly mild to moderate, mainly during the 20-week dose-escalation period, and diminishing over time.2
Why it happens
GLP-1 medicines slow digestion, which is part of how they keep you full. The 2022 consensus adds a practical reason: because people feel full, they also tend to drink less water, which can make constipation more likely.3 The 2025 joint advisory from four US nutrition and obesity societies notes that foods high in protein or fat can slow stomach emptying further and may worsen constipation.4 That matters because many people on these medicines are also trying to eat more protein. See what to eat on a GLP-1 for how to balance the two.
Constipation, then diarrhea?
Some people swing between the two. The joint advisory notes that extended constipation can lead to reactive diarrhea.4 Both are also common on their own: in STEP 1–3, 29.7% of people on semaglutide reported diarrhea at some point, alongside the 24.2% with constipation.1 If your bowel habits keep swinging, mention it to your clinician rather than treating each phase separately.
What guidance suggests for relief
We found no randomized trial testing constipation remedies specifically in people on GLP-1 medicines. What exists is expert guidance. Both sources below put the same three things first:3,4
- Fluids. The 2022 consensus advises drinking generous amounts of water or other sugar-free drinks. The advisory says adequate fluids should be encouraged.
- Fiber from food, added gradually. The advisory mentions foods with soluble and insoluble fiber, such as prunes and other dried fruit, and fruits and vegetables with a high water content.
- Moving more. The consensus advises increasing physical activity.
If diet changes are not enough, the 2025 advisory lists other options clinicians use, including magnesium supplements, fiber supplements, polyethylene glycol 3350 (the ingredient in MiraLAX) and stool softeners. It also notes that some anti-nausea medicines, such as ondansetron, can worsen constipation.4 The 2022 consensus adds that clinicians may consider lowering the GLP-1 dose if symptoms worsen.3 This article does not recommend any product or dose. Supplements and laxatives can interact with kidney problems and other medicines, so ask your clinician or pharmacist which, if any, fits you.
In the trials, few people stopped treatment over stomach side effects as a group: 4.3% on semaglutide in STEP 1–3, and 1.9% to 4.3% across Zepbound doses in SURMOUNT-1 and -2 (vs 0.5% on placebo).1,5 For nausea and the other stomach effects, see how common nausea is on a GLP-1.
When constipation is a warning sign
Most constipation on these medicines is uncomfortable but not dangerous. In STEP 1–3, 98.1% of all stomach side effects were mild or moderate.1 But the US labels for Wegovy, Ozempic and Zepbound list ileus (the gut stopping moving), intestinal obstruction and severe constipation including fecal impaction among problems reported after approval. Those reports are voluntary, so their true frequency is unknown.5
The labels instruct patients to tell their healthcare provider about stomach problems that are severe or will not go away. They also tell patients to stop the medicine and call their provider right away for severe stomach pain that will not go away, with or without vomiting, sometimes felt in the back, because it can be a sign of pancreatitis.5 These are the labels' instructions, not personal advice.
Common questions
How common is constipation on Ozempic or Wegovy?
In the STEP 1 to 3 trials of adults with overweight or obesity, 24.2% of people on semaglutide 2.4 mg (Wegovy) reported constipation over 68 weeks, compared with 11.1% on placebo. At the lower doses used for type 2 diabetes, the Ozempic label reports 5% on 0.5 mg and 3.1% on 1 mg, vs 1.5% on placebo.
Does Zepbound cause constipation?
Yes, it is one of its most common side effects. In the pooled SURMOUNT-1 and SURMOUNT-2 weight trials summarized in the Zepbound label, constipation was reported by 17%, 14% and 11% of adults on tirzepatide 5, 10 and 15 mg, compared with 5% on placebo.
How long does GLP-1 constipation last?
In the semaglutide STEP 1 to 3 trials, a constipation episode lasted a median of 47 days, compared with 35 days on placebo, much longer than nausea (8 days) or diarrhea (3 days). The share of people affected leveled off around week 10, and in the STEP 4 trial it fell gradually over time in people who stayed on treatment.
What helps constipation on a GLP-1?
A 2025 joint advisory from four US nutrition and obesity societies and a 2022 expert consensus both list fluids, fiber from food and more physical activity first. The advisory also lists supplements and over-the-counter options for when diet is not enough, but which to use, if any, is a question for your clinician.
Why do I have constipation then diarrhea on Ozempic?
The 2025 joint nutrition advisory notes that extended constipation can lead to reactive diarrhea. Both are also common side effects on their own: in the STEP 1 to 3 trials, 29.7% of people on semaglutide 2.4 mg reported diarrhea and 24.2% constipation.
Sources
- Wharton S, Calanna S, Davies M, et al. Gastrointestinal tolerability of once-weekly semaglutide 2.4 mg in adults with overweight or obesity, and the relationship between gastrointestinal adverse events and weight loss. Diabetes Obes Metab. 2022;24(1):94-105. doi:10.1111/dom.14551 · Full text (PMC)
- Rubino DM, Pedersen SD, Connery L, et al. Gastrointestinal tolerability and weight reduction associated with tirzepatide in adults with obesity or overweight with and without type 2 diabetes in the SURMOUNT-1 to -4 trials. Diabetes Obes Metab. 2025;27(4):1826-1835. doi:10.1111/dom.16176 · Full text (PMC)
- Gorgojo-Martínez JJ, Mezquita-Raya P, Carretero-Gómez J, et al. Clinical Recommendations to Manage Gastrointestinal Adverse Events in Patients Treated with Glp-1 Receptor Agonists: A Multidisciplinary Expert Consensus. J Clin Med. 2022;12(1):145. doi:10.3390/jcm12010145 · Full text (PMC)
- Mozaffarian D, Agarwal M, Aggarwal M, et al. Nutritional priorities to support GLP-1 therapy for obesity: A joint Advisory from the American College of Lifestyle Medicine, the American Society for Nutrition, the Obesity Medicine Association, and The Obesity Society. Obesity (Silver Spring). 2025;33(8):1475-1503. doi:10.1002/oby.24336 · Full text (PMC)
- US prescribing information and Medication Guides: WEGOVY, OZEMPIC, ZEPBOUND and MOUNJARO (DailyMed; 2026 versions checked November 2026). Sections 5, 6.1, 6.2 and Medication Guide.
- MedlinePlus Medical Encyclopedia. Intestinal obstruction and Ileus. US National Library of Medicine (accessed November 2026).
