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Ozempic Side Effects to Watch For

Medically reviewed by Leigh Ann Anderson, PharmD. Last updated on Jan 30, 2025.

Official Answer by Drugs.com

Ozempic (semaglutide) is a treatment for type 2 diabetes to control blood sugar (glucose) levels, it is used in addition to a healthy diet and an exercise program. Ozempic for weight loss has shown to be helpful, but is not approved by the FDA for this use.

Ozempic is also approved to:

Here, let’s look at 4 important side effects with Ozempic. Some side effects are more common than others. Luckily, the most common side effects are usually short-term and only last a few days or weeks in most people. We’ll offer tips on how you can recognize and manage these side effects so you can stay on treatment and meet your goals.

Ozempic Side Effect: Stomach problems

The most common side effects of Ozempic related to the stomach are typically mild and tend to resolve within a few weeks for most people. These stomach-related side effects may become more frequent with higher doses or when increasing the dosage.

Nausea is the most common stomach-related Ozempic side effect affecting about 15% to 20% of people.

More patients receiving Ozempic 0.5 mg (3.1%) and 1 mg (3.8%) discontinued treatment due to stomach side effects than patients receiving placebo (0.4%).

The good news is that for most people these side effects are mild, temporary and will not interfere with long-term treatment. They typically subside with a few weeks of starting treatment.

Stomach side effects usually occur at the beginning of treatment and when your dose is increased too quickly. Because of this, your healthcare provider will slowly increase your dose every 4 weeks as needed, until you reach your target dose. You can take Ozempic with or without meals.

Tips for managing Ozempic stomach side effects

To help you manage Ozempic stomach side effects:

Does Ozempic cause intestinal obstruction?

In September 2023, the FDA updated Ozempic side effects to include ileus (an intestinal obstruction) in the product label for this medicine and other similar medicines (Wegovy, Rybelsus, and Mounjaro).

The Ozempic side effect ileus was voluntarily reported in postmarketing experience after it was approved, so the FDA cannot reliably determine how often this side effect occurs or if the drug actually caused the side effect.

An ileus is an intestinal blockage that results in the failure of the intestinal contents to pass through the gut, but it doesn't involve a physical blockage. An ileus can lead to problems with the muscle or nerves found in the intestine interfere with normal muscle contractions.

Symptoms of an ileus may include:

Related: What is an ileus?

If you experience stomach side effects with this medicine that bother you, worsen or do not go away, call your healthcare provider right away for further evaluation.

Lung aspiration

All GLP-1 receptor agonists like Ozempic now have a warning for a rare increased risk of lung aspiration (food or liquid getting into your lungs) during deep sedation or general anesthesia used for procedures or surgery.

It is thought lung aspiration may occur because these drugs slow down stomach emptying, and even if you fast (avoid eating / drinking) as directed before surgery you may still have food or liquid left in your stomach, which could be breathed into your lungs while under sedation or general anesthesia

Tell all of your healthcare providers that you are taking Ozempic before you are scheduled to have surgery or any other procedure.

Ozempic Side Effect: Vision changes (diabetic retinopathy)

An Ozempic side effect is a temporary worsening of diabetic retinopathy in some patients, this could be due to rapid improvement in blood sugar control.

In a clinical study, more patients receiving Ozempic (3%) had diabetic retinopathy complications compared to the group taking a placebo (inactive) treatment (1.8%). The risk was higher in patients with a history of diabetic retinopathy (Ozempic 8.2%, placebo 5.2%) than in those without a known history of this eye disease (0.7%, placebo 0.4%).

Diabetic retinopathy is a serious eye disease that can lead to blindness. People with type 2 diabetes and long-term, uncontrolled blood sugar levels are at higher risk.

In this form of retinopathy, blood vessels weaken and leak blood into the surrounding tissues which lead to inflammation. Over time this results in new blood vessels forming that obstruct the retina and can lead to blindness.

Risk factors for developing diabetic retinopathy include: having diabetes for more than 5 years, poor blood sugar control, high blood pressure, high cholesterol, pregnancy, or kidney disease, smoking, eye surgery or other eye problems, a family history of diabetic retinopathy.

The effect of long-term blood sugar control with semaglutide on diabetic retinopathy complications has not been studied.

Tips for managing or identifying vision changes

Ozempic Side Effect: Thyroid tumors or cancer

One of the most serious but rare Ozempic warnings includes a risk for thyroid tumors or thyroid cancer, which has been seen in animal (rat) studies. It is not known if it will cause thyroid tumors or thyroid cancer in humans, but it carries a Boxed Warning for this possible side effect, the FDA’s most prominent warning.

Your thyroid is a small gland found in the front of your neck area. It helps to control many functions in your body by making and releasing certain thyroid hormones.

Cases of MTC have been seen in patients treated with another GLP-1 receptor agonist known as liraglutide (Saxenda, Victoza) after it was approved by the FDA. However, it is not known if liraglutide caused these tumors because there was not enough data in the reports to draw a final conclusion.

Your doctor will check your thyroid gland (found in your neck area) for nodules. A blood test (serum calcitonin) or a thyroid ultrasound (an imaging test) may be used to monitor for thyroid disease, but this is not commonly done because the tests are not very specific. However, if your doctor suspects thyroid disease, they may order these tests and do further evaluations.

Related questions

Tips for managing possible or identifying thyroid disease or cancer

If you notice any of the following signs or symptoms, contact your doctor right away:

Ozempic Side Effect: Low blood sugar (hypoglycemia)

The risk of hypoglycemia with Ozempic and other GLP1 receptor agonists is low, but may still occur. You may be at a greater risk for this side effect if you also take other drugs for diabetes, including sulfonylureas (for example: glipizide or glyburide) or insulin. Higher doses of Ozempic may also increase your risk for low blood sugar.

Low blood sugar, if it occurs, can be a serious side effect.

Monotherapy

In 30-week long studies, when Ozempic 0.5 mg or 1 mg dose was used as the only diabetes treatment, low blood sugar with symptoms occurred in 1.6% to 3.8% of patients taking Ozempic and 0% taking a placebo (inactive treatment). No severe hypoglycemia was reported with Ozempic monotherapy.

Use with insulin

When Ozempic is used with insulin, hypoglycemia can occur and a dose reduction of the insulin may be needed.

Use with sulfonylureas

When this medicine is used with sulfonylureas such as glipizide, glyburide or glimepiride, hypoglycemia can occur and a dose reduction of the sulfonylurea may be needed.

Low blood sugar has also been reported in patients taking GLP-1 receptor agonists who do not have type 2 diabetes.

Tips for managing or recognizing low blood sugar

Call your doctor right away if you have any of these signs or symptoms:

Ask your doctor what you should do if you develop symptoms of low blood sugar. This may include taking glucose (sugar) tablets, a glucose liquid, or fruit juice. You and your doctor may need to more closely monitor your blood sugar during treatment with Ozempic.

Tell your healthcare provider if you are taking other medicines to treat diabetes, including sulfonylureas or insulin. Ozempic slows down your stomach emptying and can affect medications that need to pass through your stomach quickly. Your doctor may need to change your dose of certain diabetes medicines.

This is not a complete list of side effects or warnings with Ozempic. Other important side effects include disease of the pancreas, gallbladder, kidney and serious allergic reactions. If you have questions or concerns about side effects, contact your doctor right away.

Click this link for all Ozempic side effects in more detail. You can also review the manufacturer’s Medication Guide and discuss this information with your healthcare provider.

Bottom Line

This is not all the information you need to know about Ozempic (semaglutide) for safe and effective use and does not take the place of your doctor’s directions. Review the full product information and discuss this information and any questions you have with your doctor or other health care provider.

References
  • Ozempic prescribing information. Revised 1/2025. Novo Nordisk. Plainsboro, NJ. Accessed Jan 30, 2025 at https://www.novo-pi.com/ozempic.pdf
  • Noura N, Pratibha R, Vinni M. Cleveland Clinic Journal of Medicine August 2022, 89 (8) 457-464; DOI: https://doi.org/10.3949/ccjm.89a.21110

Read next

How long does it take for Ozempic to work?

Your blood glucose (sugar) levels should start to fully decline within the first week after you start using Ozempic (semaglutide) at your regular dose. However, the full effect can take 8 weeks or longer, as this is a long-acting medication that is injected only once per week. Continue reading

Wegovy vs Ozempic: Which is Right for You?

Both Wegovy and Ozempic contain semaglutide, but Wegovy is prescribed for long-term weight management while Ozempic is used to control blood sugar levels in type 2 diabetes and help protect kidney function. They both lower the risk for heart-related complications, but they differ in other approved uses, doses, target populations and costs. Continue reading

How many doses are in an Ozempic pen?

Ozempic pens come in 3 sizes. Each pen holds 4 maintenance doses of either 0.5 mg, 1 mg, or 2 mg of medicine given once weekly and will last for one month. Continue reading

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