Is Wegovy Safe? Safety Profile and Potential Risks

Wegovy has quickly become one of the most widely used weight-loss medications in the UK. That’s because it’s a highly effective treatment for patients who’ve struggled to lose weight through diet and lifestyle changes alone.

But if you’re thinking about starting Wegovy, you may be worried about how safe it is.

Wegovy is safe when prescribed and used according to the manufacturer guidelines. However, as with all medicines, Wegovy has side effects, risks and important safety considerations. Patients should take this into account before starting treatment.

Here’s what you need to know.

How Wegovy Works

Wegovy (semaglutide) works by mimicking a hormone called glucagon-like peptide-1 (GLP-1). This hormone, which our bodies naturally produce, plays a role in regulating appetite.

By mimicking this hormone, Wegovy slows down gastric emptying. This means it keeps food in the stomach for longer to reduce hunger and help you feel fuller for longer.

In people with diabetes, it also boosts insulin release after meals, lowering blood glucose levels. Although semaglutide can lower blood sugar, Wegovy in the UK is licensed for weight management, not diabetes.

It can also help patients with problems including high cholesterol and heart disease that often occur alongside obesity.

Is Wegovy Safe?

Yes. Wegovy is safe and approved for use in the UK if prescribed by a healthcare professional.

The UK medicines regulator (MHRA) has approved semaglutide (the active ingredient in Ozempic and Wegovy) for treating type 2 diabetes and for weight management.

In the UK, Wegovy is licensed for weight management and reducing cardiovascular risk in obese or overweight adults with additional risk factors. Ozempic is licensed for type 2 diabetes.

The MHRA and other global regulators only approve medications that meet rigorous quality standards. Like other weight loss drugs, Wegovy’s approval is based on evidence from a number of clinical trials confirming both its safety and effectiveness, as part of a program called Semaglutide Treatment Effect in People with obesity (STEP).

However, safe use of Wegovy depends on close monitoring and gradual dose increases, adjusted depending on the patient’s response.

As a prescription-only medicine, only a qualified prescriber can prescribe it after an assessment. They will determine whether it is appropriate and safe for you. They’ll base this on your starting body weight, body mass index (BMI) and medical history. Follow-up monitoring is also important to track your progress and manage any side effects.

Like all medicines, Wegovy carries a risk of side effects. The most common include:

• Constipation
• Diarrhoea
• Fatigue
• Stomach discomfort
• Nausea and vomiting 

Most people find that these side effects are temporary and improve as the body adjusts. In some cases, side effects may persist, and you may need a lower dose. If you experience troublesome side effects, speak to your prescriber to discuss the best course of action.

Is Wegovy Safe to Use Long-Term?

Yes. The MHRA has approved Wegovy for long-term use. So it is safe to use for an extended period.

There isn’t a strict limit for how long you can use it for. But your prescriber should review your treatment regularly to ensure the benefits continue to outweigh risks.

When is Wegovy Dangerous?

Wegovy is considered safe for most patients. However, there are situations where patients won’t be suitable. Your prescriber will determine this during consultation.

People who should not use Wegovy include:

• Pregnant Patients: Wegovy is not safe to use in pregnancy because there is not enough data to determine whether it could cause harm to the unborn baby. The manufacturer also advises women of childbearing age to use effective contraception during – and for at least two months after stopping – treatment.
• Breastfeeding Patients: We don’t recommend you use Wegovy while breastfeeding. Experts don’t know whether the medicine passes into breast milk.
• People with Severe Kidney or Liver Problems: This can make it harder to clear the drug effectively. So Wegovy may not be suitable.
• Those With a History of Pancreatitis: There is a link between GLP-1 drugs and a risk of pancreatitis.
• Patients with a Personal or Family History of Certain Thyroid Cancer: This includes medullary thyroid carcinoma (MTC). Or multiple endocrine neoplasia syndrome type 2 (MEN2).

This list is not exhaustive, so your prescriber will use their clinical judgment to decide if Wegovy is right for you. They will also take into account existing medication you’re using.

Serious Side Effects of Wegovy

Serious side effects are rare, but they can occur. If you have symptoms of the following side effects, seek urgent medical attention:

• Acute Pancreatitis (Inflammation of the Pancreas): Symptoms include severe and abdominal pain – sudden, sharp, or burning pain in the upper abdomen, often radiating to the back, which may worsen after eating. Other symptoms include jaundice, persistent nausea and/or vomiting, and steatorrhea (fatty stools – pale, bulky, foul-smelling stools due to poor fat digestion).
• Gallbladder Diseases (Gallstones, Inflammation of the Gallbladder): Symptoms of gallstones include stomach pain, according to the NHS. The pain may feel severe, be constant, last longer than 30 minutes (up to several hours). It might be in the middle of your tummy, or just under your ribs on the right side. It may make you feel sick or vomit. The main symptom of gallbladder inflammation is a sudden, sharp pain in the upper right-hand side of your tummy. This pain spreads towards your right shoulder.
• Severe Allergic Reactions: Get medical help right away if you have trouble breathing. You might experience lumps or swelling in your face, lips, tongue, or throat. You may also have difficulty swallowing, wheezing, a fast heartbeat, pale or cold skin, and feel dizzy or weak.

How to Use Wegovy Safely

Before starting treatment, you will have a consultation with a healthcare professional. This will confirm that Wegovy is appropriate for you.

For Wegovy to be safe, you also need to use it according to the prescriber’s instructions. If prescribed, patients will take Wegovy as a once-weekly injection with a gradual increase in dose.

It usually follows this schedule:

• Weeks 1 to 4: 0.25 mg once weekly
• Weeks 5 to 8: 0.5 mg once weekly
• Weeks 9 to 12: 1 mg once weekly
• Weeks 13 to 16: 1.7 mg once weekly
• Week 17 onwards: 2.4 mg once weekly

Your provider may increase your dose more slowly, depending on how well you tolerate the medicine. Regular follow-ups with your healthcare provider are essential to monitor your progress. Your provider will adjust your dose if needed, and provide support throughout your treatment.

Buying Wegovy Safely

With Wegovy’s growing popularity, there has been a surge in counterfeit and unregulated products being sold online. These fake versions may be ineffective, contaminated, or even harmful. For your safety, always ensure you buy from a registered UK pharmacy.

Here’s how to make sure you’re buying from a legitimate provider:

• Check the GPhC Registration: All UK pharmacies must be registered with the General Pharmaceutical Council (GPhC). You can usually find this at the bottom of the website or search for the pharmacy on the GPhC pharmacy register.

• Look for an Assessment: Wegovy is a prescription-only medicine. Only a qualified prescriber can prescribe it after an assessment.

• Verify Prescriber Details: The qualified professional prescribing Wegovy should have their professional GPhC registration number visible.

• Check for UK Contact Details: A real pharmacy will have a UK-based address, a phone number, and a professional email you can contact.

Key Takeaways

• Wegovy is a Safe and Effective Weight Loss Medication: When prescribed and monitored by a healthcare professional. Wegovy is effective, but it is not a quick fix. It works best alongside a healthy diet and physical activity.
• It Works by Mimicking GLP-1: This reduces appetite, slows digestion, and regulates blood sugar levels. Alongside a healthy diet and physical activity, this can help you lose and manage your weight.
• Side Effects: Common side effects of Wegovy are usually temporary. But serious risks exist, making medical supervision essential.
• Wegovy is Not Suitable for Everyone: For pregnant or breastfeeding women, it’s not safe. Those with certain health conditions should also avoid Wegovy.
• Buy Safely: Wegovy is a genuine licensed medicine made by Novo Nordisk. Always buy Wegovy from a registered UK pharmacy to avoid counterfeit medicines.

References

Wegovy 2.4 mg, FlexTouch solution for injection in pre-filled pen – Summary of Product Characteristics (SmPC) – (emc) | 13803. (n.d.). https://www.medicines.org.uk/emc/product/13803/smpc.

JackW. (n.d.). Semaglutide – Uses, How it Works and Side Effects. Diabetes UK. https://www.diabetes.org.uk/about-diabetes/looking-after-diabetes/treatments/tablets-and-medication/semaglutide.

Kommu, S., & Whitfield, P. (2024, February 11). Semaglutide. StatPearls – NCBI Bookshelf. https://www.ncbi.nlm.nih.gov/books/NBK603723/.

Wilding, J. P., Batterham, R. L., Calanna, S., Davies, M., Van Gaal, L. F., Lingvay, I., McGowan, B. M., Rosenstock, J., Tran, M. T., Wadden, T. A., Wharton, S., Yokote, K., Zeuthen, N., & Kushner, R. F. (2021). Once-Weekly Semaglutide in Adults with Overweight or Obesity. New England Journal of Medicine, 384(11), 989–1002. https://doi.org/10.1056/nejmoa2032183.

and, M. (2025). Women on ‘skinny jabs’ must use effective contraception, MHRA urges in latest guidance. [online] GOV.UK. Available at: https://www.gov.uk/government/news/women-on-skinny-jabs-must-use-effective-contraception-mhra-urges-in-latest-guidance.

Semaglutide | Drugs | BNF content published by NICE. (n.d.). https://bnf.nice.org.uk/drugs/semaglutide.

NHS (2019). Acute cholecystitis. [online] NHS. Available at: https://www.nhs.uk/conditions/acute-cholecystitis.

NHS (2019). Gallstones. [online] NHS. Available at: https://www.nhs.uk/conditions/gallstones.