Can Ozempic cause seizures? What a 10,000-patient study found

The short answer

No. There is no good evidence that Ozempic or other GLP-1 drugs cause seizures, and a large 2026 study found the opposite: adults with type 2 diabetes who started semaglutide had a lower rate of new adult-onset seizures than those on other diabetes drugs. The catch is that this is early, association-level evidence built on a small number of events, not proof that the drug protects your brain. And it does not touch the one seizure risk on these medications that is genuinely worth your attention, which runs through severe nutrient depletion, not the drug itself.

If you have searched "can Ozempic cause seizures," you have probably seen two worries tangled together: that the drug might trigger a seizure, and that its dramatic effect on blood sugar might do the same. A new study in the journal Neurology is the best data we have on the first question, and the answer is reassuring. The second question, about blood sugar, the researchers deliberately set aside, and that turns out to matter.

What the 2026 Neurology study found

Researchers used the All of Us Research Program, a large US database of health records, to run what is called a target trial emulation. In plain terms, they built matched groups from real patient data to mimic a randomized trial: adults with type 2 diabetes who newly started semaglutide, compared against adults who started other glucose-lowering drugs. One comparison involved 10,213 people. A second compared semaglutide against SGLT2 inhibitors, a different diabetes drug class, in 8,605 people. They then counted new cases of adult-onset seizure over up to four years, and, importantly, they excluded seizures caused by low blood sugar.

The semaglutide group had fewer seizures in both comparisons.

• Against other diabetes drugs, semaglutide was linked to a 56 percent lower rate of new seizures (hazard ratio 0.44, 95 percent confidence interval 0.25 to 0.79). Over four years that came to about 1.78 fewer seizure cases per 100 people, with a number needed to treat of 70.
• Against SGLT2 inhibitors, the reduction was similar: a hazard ratio of 0.48 (0.27 to 0.85), or roughly 1.46 fewer cases per 100 people.

The effect also looked independent of weight loss and blood sugar control. When the researchers tested how much of the benefit ran through changes in HbA1c or BMI, the answer was almost none, a few percent at most. Whatever is going on, it does not appear to be a simple by-product of losing weight.

Why the result is not as strong as the headline

Here is the uncomfortable part, and the study's own authors lead with it. This is an association, not proof, and they describe their findings as "hypothesis-generating rather than practice-changing." A few reasons to keep your expectations in check:

• Very few seizures actually happened. In the main comparison there were only about two dozen seizure cases in the semaglutide group. When the numbers are that small, one cluster of events can swing the result, and the authors say the effect size may be inflated by the low counts.
• The benefit was almost entirely in men. This is the strangest finding in the paper. In men, semaglutide was linked to a 92 percent lower seizure rate (hazard ratio 0.08). In women, there was no significant effect at all (hazard ratio 0.77, a result that could easily be chance). No one knows why, and a genuine drug effect should not usually split this cleanly by sex.
• Follow-up was short and uneven. People on semaglutide were tracked for less time on average than the comparison groups, which can distort this kind of analysis.
• The study rated its own evidence as Class II. That is the level neurologists assign to a well-run observational study, a step below the randomized trials that change clinical practice.

The authors are honest that a direct anti-seizure effect "cannot be fully excluded," but neither can hidden differences between the groups. Early findings suggest semaglutide is not raising seizure risk, and might even lower it. That is a long way from a reason to take it for your brain.

So where does the real seizure risk come from?

Notice what the study left out: seizures caused by low blood sugar. That was a deliberate choice, because GLP-1 drugs on their own rarely drop blood sugar to dangerous lows. They mainly prompt the pancreas to release insulin when blood sugar is high, so the hypoglycemia risk is low unless a GLP-1 is paired with insulin or a sulfonylurea. But that exclusion points straight at the one seizure-adjacent danger on these medications that is genuinely worth watching, and it has nothing to do with the drug touching your brain. It runs through nutrition.

When a GLP-1 drug causes weeks of relentless nausea, vomiting or almost no eating, the body can run short on the nutrients the brain and nerves need to stay stable. Two shortages matter most here. A severe lack of thiamine (vitamin B1) can cause Wernicke encephalopathy, a brain emergency that, in serious cases, can include seizures. And steep losses of fluid and salts from vomiting or diarrhea can drop blood levels of sodium, magnesium or calcium low enough to provoke a seizure in anyone, on any medication.

This is the same indirect chain Shield has written about with nerve damage: not the drug poisoning you, but extreme GI side effects starving the system of what it needs. If you want the detail on the vitamin B1 side of it, see our piece on Wernicke encephalopathy and the vitamin B1 risk. The lesson is the same across both: the medicine is not the threat, prolonged malnutrition is.

What actually protects you

The seizure question splits neatly in two. The direct risk from the drug looks low, maybe even protective, but the evidence is early. The indirect risk, from severe nutrient depletion, is real but almost entirely preventable. A handful of habits keep you on the safe side of that line.

• Do not push through weeks of vomiting. Persistent nausea or vomiting is a reason to call your clinician, not to wait out. A slower dose increase or anti-nausea medication usually settles it before it threatens your nutrition.
• Keep food and fluids going. Small, frequent, protein-forward meals plus steady hydration protect both your nutrient stores and your electrolyte balance, which is exactly what guards against deficiency-driven seizures.
• Mind the B vitamins, especially thiamine. If your intake has dropped sharply, ask your clinician about a B-complex or multivitamin and about blood tests for thiamine, vitamin B12 and folate. Nutrient deficiency on GLP-1 is common enough to check for, not assume away.
• Do not stop a seizure medication on your own. If you already take an anti-seizure drug, nothing in this research is a reason to change it. Talk to the doctor who prescribes it.
• Treat a first-ever seizure as an emergency. A new seizure always needs urgent medical assessment, whatever medication you are on.

Keeping your nutrition intact while a GLP-1 does its main job is the exact problem GLP-1 Shield is built around. Supplements do not treat or prevent seizures, and they are no substitute for medical care, but closing a real nutrient gap before it becomes a crisis is the point. For the wider picture, our overview of GLP-1 side effects and our monitoring guide for vitamins on GLP-1 are good next reads.

Key takeaways

• There is no good evidence that Ozempic, Wegovy or other GLP-1 drugs cause seizures.
• A 2026 Neurology study of 10,213 adults with type 2 diabetes linked semaglutide to a lower rate of new adult-onset seizures (hazard ratio 0.44), but the authors call it hypothesis-generating, not proof.
• The benefit showed up almost entirely in men and rested on very few seizure cases, so it needs confirmation in a randomized trial.
• The study excluded low-blood-sugar seizures; GLP-1 drugs rarely cause dangerous lows on their own.
• The real, preventable risk is indirect: prolonged vomiting and poor eating can deplete thiamine and electrolytes enough to provoke a seizure, so keep eating, stay hydrated, and do not tough out weeks of vomiting.

Frequently asked questions

Can Ozempic cause seizures?

There is no good evidence that Ozempic causes seizures. A 2026 study in Neurology of 10,213 adults with type 2 diabetes actually found a lower rate of new seizures on semaglutide than on other diabetes drugs. That finding is early and association-level, not proof. GLP-1 drugs also rarely cause the dangerously low blood sugar that can trigger a seizure, as long as they are not combined with insulin or certain other diabetes medications.

Does Ozempic lower seizure risk?

A 2026 Neurology study linked semaglutide to about half the rate of new adult-onset seizures in adults with type 2 diabetes (hazard ratios 0.44 and 0.48), independent of weight loss. But the benefit appeared almost only in men, rested on about two dozen cases, and the authors rate it as hypothesis-generating rather than practice-changing. It is not a reason to take a GLP-1 drug for seizure protection.

Can low blood sugar from Ozempic cause a seizure?

On their own, GLP-1 drugs like Ozempic rarely cause blood sugar low enough to trigger a seizure, because they mainly prompt insulin when blood sugar is high. The risk rises if a GLP-1 is combined with insulin or a sulfonylurea. The 2026 Neurology study deliberately excluded low-blood-sugar seizures when it found a lower overall seizure rate on semaglutide.

What is the real seizure-related danger on a GLP-1 drug?

It is indirect and preventable. Weeks of severe vomiting or very low eating can drain thiamine (vitamin B1) and drop electrolytes like sodium and magnesium low enough to provoke a seizure. A severe thiamine shortage can also cause Wernicke encephalopathy, a brain emergency. Do not push through prolonged vomiting; keep eating small amounts, stay hydrated, and seek care if symptoms are severe.