What are the most common side effects of Ozempic?

Side effects occur in more than 1 in 10 people using Ozempic¹. The good news is that these are usually mild to moderate and resolve on their own. By far, most side effects involve the gastrointestinal system. This is because Ozempic slows gastric emptying - exactly the mechanism that helps with weight loss².

The most common Ozempic side effects are:

• Nausea – up to 44% of users, especially at the start

• Diarrhea – approximately 30% of users

• Vomiting – approximately 24% of users

• Constipation – approximately 20% of users

• Fatigue – approximately 11% of users

These percentages come from clinical trials with semaglutide¹˒³. It’s important to understand that not everyone experiences all side effects. Many people have only one or two symptoms, and some experience none at all.

The reason these side effects occur is closely related to how Ozempic works. By slowing gastric emptying, food stays in your stomach longer. This creates the feeling of fullness that supports weight loss, but it can also temporarily cause gastrointestinal symptoms while your body adjusts².

How long do the side effects last?

Most side effects are strongest during the first 4 to 8 weeks after starting Ozempic¹. You’ll notice them particularly shortly after your first injections and when your dose is increased. This is normal: your body needs time to adapt to the medication.

The good news: for most people, side effects such as nausea, diarrhea, and vomiting disappear within a few days to a few weeks³. As your body becomes accustomed to the delayed gastric emptying, symptoms usually decrease gradually.

Not everyone has the same experience. Some people notice improvement after just one week, while others need more time. If you are still experiencing severe side effects after 4 to 6 weeks, it’s advisable to contact your doctor. Your dose may need adjustment, or other solutions may be available.

Important to remember: temporary side effects do not mean that Ozempic isn’t working for you. They usually indicate that your body is adapting to the medication.

How can you reduce Ozempic side effects?

Most Ozempic side effects can be managed effectively with practical adjustments to your daily routine. Here are concrete tips that truly help:

For nausea:

• Eat smaller portions more frequently (5–6 small meals instead of 3 large ones)

• Drink ginger or peppermint tea – these have a natural soothing effect on the stomach

• Go outside for fresh air when you feel nauseous

• Avoid heavy, fatty, or fried foods

• Eat slowly and chew thoroughly

• Try not to skip meals

For diarrhea:

• Drink extra water – at least 2 to 3 liters per day to prevent dehydration

• Avoid coffee, alcohol, and very fatty foods

• Eat mild foods such as bananas, rice, applesauce, and toast (BRAT diet)

• Consider probiotics to support gut health

• If diarrhea lasts longer than a week, contact your doctor

For constipation:

• Increase your fiber intake – eat more vegetables, fruit, and whole grains

• Drink enough water (2–3 liters per day)

• Exercise regularly – walking helps stimulate bowel movement

• Consider fiber supplements if needed

• Don’t wait too long – go to the bathroom as soon as you feel the urge

General tips:

• Avoid alcohol, especially during the first weeks after starting Ozempic

• Take your injection on the same day each week so your body develops a rhythm

• Increase the dose gradually as prescribed – increasing too quickly causes more side effects

• Stay well hydrated – this helps with nearly all side effects

• Give your body time – most side effects lessen after a few weeks

What serious side effects of Ozempic should you watch for?

Although most side effects are mild, there are some rare but serious side effects you should be aware of. It’s important to know these - not to worry you, but to recognize when to seek immediate medical attention.

Pancreatitis (inflammation of the pancreas) – up to 1% of users

Symptoms: Severe, persistent pain in the upper abdomen that may radiate to your back, sometimes accompanied by nausea and vomiting⁵. If this occurs, stop Ozempic and contact your doctor immediately.

Gallbladder problems

Rapid weight loss can increase the risk of gallstones.
Symptoms: Severe pain in the upper right abdomen, especially after eating. Contact your doctor if you experience this.

Hypoglycemia (low blood sugar)

This mainly occurs in people with diabetes who also use other blood sugar–lowering medications⁶.

Symptoms: Shaking, sweating, palpitations, confusion, hunger. Eat or drink something sweet and inform your doctor.

Severe allergic reaction – up to 0.1% of users

Symptoms: Swelling of the face, lips, tongue, or throat; difficulty breathing; widespread rash. This is a medical emergency - call 112 immediately.

Also contact your doctor if you experience:

• Changes in vision

• Signs of thyroid problems (a lump in the neck, difficulty swallowing, hoarseness)

• Severe or persistent abdominal pain

• Kidney problems (little or no urine, swelling of ankles or feet)

Who is Ozempic not suitable for?

Not everyone can use Ozempic safely. Your doctor will thoroughly review your medical history before prescribing Ozempic⁶.

Ozempic is not suitable if you:

• Have a personal or family history of medullary thyroid carcinoma (a rare type of thyroid cancer)

• Have Multiple Endocrine Neoplasia syndrome type 2 (MEN 2)

• Have a severe allergy to semaglutide or any other ingredients in Ozempic

• Have type 1 diabetes (Ozempic is only for type 2 diabetes)

• Are pregnant, planning to become pregnant, or breastfeeding

• Have a history of pancreatitis (extra caution required)

Extra caution is also needed in people with:

• Severe gastrointestinal conditions (such as gastroparesis)

• Kidney problems or kidney failure

• Liver disease

• A history of depression or suicidal thoughts

Also inform your doctor about all medications you are taking. Ozempic can interact with certain other drugs, especially other diabetes medications⁶.

Is Ozempic safe for long-term use?

The STEP trials have extensively studied the safety of semgaglutide, the active ingredient in Ozempic. These studies followed the safety and effectiveness of semaglutide for up to 2 years⁴. The results show that Ozempic is safe for most people over this period, provided it is used under medical supervision.

An important point: in people with type 2 diabetes and cardiovascular disease, research has shown that semaglutide can reduce the risk of major cardiovascular events such as heart attacks and strokes⁵. This means that for many people, the benefits clearly outweigh the potential side effects.

That said, Ozempic is intended for long-term use with ongoing medical supervision. Regular check-ups with your doctor are essential to monitor your response to the medication and to detect any side effects early.

The safety of very long-term use (beyond 2 years) is still being studied, but current evidence suggests that Ozempic remains safe for most people when used correctly⁴.

Curious whether you qualify for Ozempic?

Start the medical intake today and discover which treatment suits you best. The physicians at Menkind are ready to personally guide you through your weight loss journey.

References

1. European Medicines Agency. (2024). Ozempic (semaglutide): EPAR - Productinformatie. https://www.ema.europa.eu/en/documents/product-information/ozempic-epar-product-information_en.pdf

2. Blundell, J., Finlayson, G., Axelsen, M., et al. (2017). Effects of once-weekly semaglutide on appetite, energy intake, control of eating, food preference and body weight in subjects with obesity. Diabetes, Obesity & Metabolism, 19(9), 1242–1251. https://pubmed.ncbi.nlm.nih.gov/28266779/

3. Davies, M., Færch, L., Jeppesen, O. K., et al. (2021). Semaglutide 2.4 mg once a week in adults with overweight or obesity, and type 2 diabetes (STEP 2): a randomised, double-blind, double-dummy, placebo-controlled, phase 3 trial. Lancet, 397(10278), 971–984. https://pubmed.ncbi.nlm.nih.gov/33667417/

4. Garvey, W. T., Batterham, R. L., Bhatta, M., et al. (2022). Two-year effects of semaglutide in adults with overweight or obesity: the STEP 5 trial. Nature Medicine, 28, 2083–2091. https://pubmed.ncbi.nlm.nih.gov/36216945/

5. Marso, S. P., Bain, S. C., Consoli, A., et al. (2016). Semaglutide and cardiovascular outcomes in patients with type 2 diabetes. The New England Journal of Medicine, 375(19), 1834–1844. https://pubmed.ncbi.nlm.nih.gov/27633186/

6. Kommu, S. & Whitfield, P. (2024). Semaglutide. StatPearls. https://www.ncbi.nlm.nih.gov/books/NBK603723/