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Zepbound side effects
Nausea tops Zepbound’s label table at 25, 29 and 28 in every 100 people on 5, 10 and 15 mg, against 8 on placebo.
Source for this answer
Source: Read from the Zepbound label, revision 08/2026
Source: Read from the Zepbound label, revision 08/2026
Medically reviewed by Jennifer Montecillo, MD · non-practicing medical reviewerReviewed 2026-08-12every number here is sourced
The two placebo-controlled weight trials, dose by dose
Read the placebo column first. Nearly everything below also happened to some people on placebo. The gap between columns is the part linked to the drug in these trials.
Trial armsPlacebo: n = 958Zepbound 5 mg: n = 630Zepbound 10 mg: n = 948Zepbound 15 mg: n = 941
| Side effect | Placebo | Zepbound 5 mg | Zepbound 10 mg | Zepbound 15 mg |
|---|---|---|---|---|
| Nausea | 8% | 25% | 29% | 28% |
| DiarrheaGroups diarrhea and frequent bowel movements | 8% | 19% | 21% | 23% |
| Vomiting | 2% | 8% | 11% | 13% |
| ConstipationGroups constipation and hard stools | 5% | 17% | 14% | 11% |
| Belly pain | 5% | 9% | 9% | 10% |
| Indigestion | 4% | 9% | 9% | 10% |
| Reactions where you injectGroups bruising, redness, itching, pain and rash at the injection site | 2% | 6% | 8% | 8% |
| Tiredness | 3% | 5% | 6% | 7% |
| Allergic reactions | 3% | 5% | 5% | 5% |
| Burping | 1% | 4% | 5% | 5% |
| Hair loss | 1% | 5% | 4% | 5% |
| Acid reflux | 2% | 4% | 4% | 5% |
| Wind | 2% | 3% | 3% | 4% |
| Bloating | 2% | 3% | 3% | 4% |
| Dizziness | 2% | 4% | 5% | 4% |
| Low blood pressureGroups low blood pressure and blood pressure drops on standing | 0% | 1% | 1% | 2% |
The boxed warning: thyroid tumors in rodents
Zepbound opens with a boxed warning about thyroid C-cell tumors found in rats. It is not known whether tirzepatide does the same in people. The label rules the drug out where medullary thyroid cancer runs in the family, and where someone has the inherited condition MEN 2.
What does the label tell prescribers to watch for?
These warnings sit above the table in the label. They cover uncommon problems that matter most.
| Warning | What this label says about it |
|---|---|
| Pancreatitis | The label says to stop if it is suspected. |
| Gallbladder disease | Reported more often than on placebo in the weight trials. |
| Severe stomach and gut problems | Reported by 1.7, 2.5 and 3.1 in every 100 people on 5, 10 and 15 mg, against 1 on placebo. This is one of the few places the label shows a clean rise with the dose. |
| Low blood sugar | Mainly where Zepbound is taken alongside insulin or a sulfonylurea. |
| Kidney injury | Usually following fluid loss. |
| Serious allergic reactions | The label lists these separately from the milder ones in the table. |
| Diabetic eye disease | Relevant to the quarter of the trial population who had type 2 diabetes. |
| Breathing in stomach contents under anesthetic | The label tells anesthetists not to assume the stomach is empty. |
What matters first
- Highest listed reaction
- Nausea: 29% in Zepbound 10 mg
- Distinct reactions listed
- 16
- Warnings to watch
- 8
- Boxed warning
- The boxed warning: thyroid tumors in rodents
What have people actually reported about Zepbound?
70,141 reports naming Zepbound have reached the FDA’s public database. A report is not proof the drug caused anything, and there is no way to know how many people took it.
| Most reported | Reports | Share of Zepbound reports |
|---|---|---|
| Wrong dose given | 12,768 reports | 18% of Zepbound reports |
| Nausea | 7,913 reports | 11% of Zepbound reports |
| Injection site pain | 4,792 reports | 6.8% of Zepbound reports |
| Drug ineffective | 4,602 reports | 6.6% of Zepbound reports |
| Extra dose given | 4,527 reports | 6.5% of Zepbound reports |
| Diarrhea | 4,360 reports | 6.2% of Zepbound reports |
| Vomiting | 3,496 reports | 5.0% of Zepbound reports |
| Constipation | 3,026 reports | 4.3% of Zepbound reports |
| Accidental underdose | 2,612 reports | 3.7% of Zepbound reports |
| Fatigue | 2,444 reports | 3.5% of Zepbound reports |
The FDA reports include dosing errors alongside symptoms such as nausea. An error report describes how the product was used; it is not itself a side effect.
These brand-level counts do not isolate a particular device or show why an error happened. They cannot establish that one presentation causes more errors than another.
4Interpret the page
The side effects do not simply rise with the dose
Nausea peaks at 10 mg, not at 15. Constipation runs the other way entirely: 17 in 100 at 5 mg, falling to 11 at 15 mg.
The rows do not all rise with each assigned dose. That does not rule out symptoms after a dose increase for an individual.
The label says nausea, vomiting and diarrhea often occurred while doses increased, then became less common over time. Stopping because of a reaction rose from 4.8 to 6.3 to 6.7 in 100 across the three dose groups.
The sleep apnea trials did not produce a separate table
467 adults with moderate to severe sleep apnea and obesity took part in two more trials, one in people using a breathing machine and one in people who were not.
The label says the safety findings on 10 mg and 15 mg were similar to those in the weight trials. It does not provide a separate common-side-effect table for sleep apnea.
Why do Zepbound and Mounjaro report different numbers for the same drug?
Both are tirzepatide. The percentages differ because the trials behind them differ, not because one product is gentler than the other.
Each label opens its table with the same warning: rates from one drug’s trials cannot be set against another’s. That holds here even though the drug substance is identical. The two sets of trials enrolled different people. They ran to different doses. And they used different cut-offs for what got printed at all.
Where to read next
Two pages carry the parts this one leaves out.
- The Zepbound dose schedule has the step pattern these percentages are attached to.
- Side effects of tirzepatide itself covers the drug across every product built on it.
Questions readers ask
Is Zepbound safer than Ozempic?
Is Zepbound safer than Ozempic?
The cited trials do not establish that Zepbound is safer than Ozempic. SURMOUNT-5 studied weight-management doses, while SURPASS-2 studied adults with type 2 diabetes.
Comparing the two labels directly does not work either. Each set of percentages comes from a different population under a different reporting cut-off.
What not to do when taking Zepbound?
What not to do when taking Zepbound?
The label says never to share a pen and to tell the care team before anesthesia or deep sedation. It also advises against combining Zepbound with other tirzepatide products or GLP-1 medicines.
Nausea, vomiting and diarrhea often occurred during dose increases in the trials. A group average cannot rule out a dose-related problem for one person.
Are there any long-term side effects from Zepbound?
Are there any long-term side effects from Zepbound?
The main common-side-effect table covers treatment for up to 72 weeks. The label also describes a trial in which some participants continued Zepbound for up to 88 weeks.
These study periods are not yearly risk estimates. The label reports common reactions, serious warnings and later reports separately because each answers a different question.
How much weight can you lose on Zepbound in 3 months?
How much weight can you lose on Zepbound in 3 months?
The trial averages do not predict one person’s weight change after three months. The early months include dose increases, and the label does not require everyone to reach the maximum.
SURMOUNT-5 reported an average loss of 20.2% after 72 weeks with tirzepatide 10 or 15 mg. It studied adults with obesity who did not have type 2 diabetes.
- ZEPBOUND (tirzepatide) injection — DailyMed SPL, sections 5 and 6.1retrieved 2026-09-13FDA label