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Ozempic side effects, as its own label reports them

Ozempic’s label reports nausea in 20.3 of every 100 people on the 1 mg dose, and 15.8 on 0.5 mg, against 6.1 on placebo.

Source: Read from the Ozempic label, revision 06/2026

What matters first

Highest listed reaction
Nausea: 20.3% in Ozempic 1 mg
Distinct reactions listed
5
Warnings to watch
9
Boxed warning
The boxed warning: thyroid tumors in rodents

Medically reviewed by Jennifer Montecillo, MD · non-practicing medical reviewerReviewed 2026-08-12every number here is sourced

The two placebo-controlled diabetes trials

Read the placebo column first. Nearly everything below happens to some people on a dummy injection too, and the gap between the columns is the part the drug is answerable for.

Trial armsPlacebo: n = 262Ozempic 0.5 mg: n = 260Ozempic 1 mg: n = 261

The two placebo-controlled diabetes trials
Side effectPlaceboOzempic 0.5 mgOzempic 1 mg
Nausea6.1%15.8%20.3%
Vomiting2.3%5%9.2%
Diarrhea1.9%8.5%8.8%
Belly pain4.6%7.3%5.7%
Constipation1.5%5%3.1%
Who was in the trials
521 adults with type 2 diabetes took Ozempic across two trials, one on its own and one alongside background insulin. The average age was 56 and people had had diabetes for about 9 years.
How long
An average of 32.9 weeks on the drug
What made the table
Everything reported by 5 in 100 people or more, and more often than on placebo. Low blood sugar is counted separately.
Who stopped
The label reports that in the wider pool of seven trials, and in the two-year heart outcomes trial, the kinds and rates of common side effects looked like the table above.

The boxed warning: thyroid tumors in rodents

Ozempic carries the same boxed warning as every product in this family. Rats and mice given semaglutide grew thyroid C-cell tumors, and nobody knows whether people do. The label says the drug is not for anyone whose family has had medullary thyroid cancer, or who has the inherited condition MEN 2.

What does the label tell prescribers to watch for?

These sit above the table in the label, in the section reserved for the problems that are rare but matter most.

Warnings and precautions from the Ozempic FDA label
WarningWhat this label says about it
PancreatitisThe label lists it among the reasons to stop.
Diabetic eye diseaseThis gets its own warning here, because the trial population had diabetes and 8.9 in 100 already had eye damage at the start.
Low blood sugarThe risk rises when Ozempic is taken with insulin or a sulfonylurea, and the label says those doses may need cutting.
Kidney injuryUsually after fluid loss from being sick or having diarrhea.
Severe stomach and gut problemsAdded to the label in October 2025.
Gallbladder diseaseIncluding gallstones and inflammation.
Serious allergic reactionsIncluding swelling of the face and throat.
Breathing in stomach contents under anestheticThe label warns anesthetists that the stomach may not be empty.
Sharing a penThe label warns that an Ozempic pen must never be shared, even with the needle changed, because of infection risk.

What have people actually reported about Ozempic?

66,161 reports naming Ozempic 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 terms for Ozempic in openFDA FAERS, retrieved 2026-08-17
Most reportedReportsShare of Ozempic reports
Nausea9,751 reports15% of Ozempic reports
Off label use6,949 reports11% of Ozempic reports
Vomiting6,341 reports9.6% of Ozempic reports
Diarrhea5,980 reports9.0% of Ozempic reports
Decreased appetite4,507 reports6.8% of Ozempic reports
Constipation4,406 reports6.7% of Ozempic reports
Weight decreased4,157 reports6.3% of Ozempic reports
Impaired gastric emptying3,431 reports5.2% of Ozempic reports
Product used for an unapproved purpose3,294 reports5.0% of Ozempic reports
Blood glucose increased2,962 reports4.5% of Ozempic reports

Ozempic has by far the oldest report pile of the four, which matters: it has been on sale since 2017 and has had years longer to collect reports.

Two entries near the top are about how the drug is being used rather than what it did. One is use outside the label. The other is use for something it is not approved for. That is the weight-loss story showing up in the page.

  • There is no denominator. FAERS counts reports that were filed. It does not count the people who took the drug, so there is no bottom half to the fraction. Any figure on this page that looks like a percentage is a share of this drug’s reports — never a share of the people who took it.
  • A report is not proof the drug did it. FDA does not require a reporter to establish cause. A report says somebody noticed something and thought the drug was worth naming. Some of these events were caused by the drug, some were caused by the illness it was prescribed for, and some were coincidence — FAERS does not separate them.
  • A bigger number can just mean a more-prescribed drug. More reports can simply mean that more people use the drug, that it is newer, or that it receives more news and legal attention. Raw report totals do not tell you which drug is safer.
  • The same event can be counted twice. One event can reach FAERS through more than one channel — the patient, the prescriber and the manufacturer can all file. FDA does not guarantee that the public files are de-duplicated.
  • Retrieved 2026-08-17 from https://api.fda.gov/drug/event.json. FDA disclaimer: Do not rely on openFDA to make decisions regarding medical care. While we make every effort to ensure that data is accurate, you should assume all results are unvalidated. We may limit or otherwise restrict your access to the API in line with our Terms of Service.
4Interpret the pageDose patterns, same-drug context, and where the evidence continues

The 2 mg dose is not in the table

The figures above cover 0.5 mg and 1 mg. The 2 mg dose only joined the label in March 2022, after the trials that built this table had finished.

What the label says about it is narrower: in a 40-week trial of 959 people taking 1 mg or 2 mg alongside metformin, no new safety problems turned up. That is a real finding, and it is not the same as a percentage.

Why Ozempic’s numbers look lower than Wegovy’s

Three things separate them, and none is that one drug is gentler.

The doses differ: this table tops out at 1 mg, while Wegovy’s tops out at 2.4 mg. The people differ too. These were adults with long-standing type 2 diabetes, not adults being treated for obesity.

The cut-off differs as well. Ozempic prints everything at 5 in 100 and above. Wegovy prints everything at 2 and above. So an effect landing between those two lines shows up on one label and not the other.

The labels themselves open with the warning that rates from one drug’s trials cannot be lined up against another’s. That applies here even though the drug substance is the same.

Why do Ozempic and Wegovy report different numbers for the same drug?

Both are semaglutide. 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.

The Wegovy side-effect table in full

Where to read next

Two pages carry the parts this one leaves out.

Questions readers ask

What are the long-term side effects of taking Ozempic?

The label does not publish a long-term table. Its side-effect figures come from two placebo-controlled diabetes trials averaging 32.9 weeks on the drug.

Ozempic has been sold since 2017, so its FDA report pile is the oldest of the four brands. That pile counts reports, not people at risk, so it cannot be read as a rate over time.

Can I just stop taking Ozempic?

The label sets out no taper and describes no withdrawal syndrome, so stopping is not treated as a medical event in itself.

It does name reasons a prescriber stops the drug, pancreatitis among them. Whether to stop, and what happens to blood sugar afterwards, is a decision for the person who wrote the prescription.

What I wish I knew before taking Ozempic?

Three things sit on the label and surprise almost everyone. The 0.25 mg starting dose is not a treatment dose. The 2 mg dose is not in the side-effect table, because it joined the label in March 2022 after those trials had finished.

And the percentages come from adults with long-standing type 2 diabetes, not from people taking it for weight. The label opens by warning that trial rates cannot be lined up against another drug’s, and the same caution applies to a different population.

How do you feel after an Ozempic injection?

Nobody has published this as a timeline. The label records whether an effect happened at all during a trial, not the hours or days it happened in.

What it does record is how often. Nausea reached 20.3 in every 100 people on 1 mg and 15.8 on 0.5 mg, against 6.1 on placebo. Vomiting, diarrhea, belly pain and constipation follow below it.

1primary source, each with the day we read it — open the documents used on this page

Ozempic is a registered trademark of its manufacturer. This page is not written, reviewed or endorsed by them. It reports figures from a public FDA label and from the FDA’s own report database, and it is not medical advice.

Beyond the Ozempic reaction table