Wegovy Explained: What Patients Need to Know Before Starting

Wegovy, also known as semaglutide, is one of the most widely discussed weight loss medications currently available in the UK. It is part of a group of treatments that work with the body’s natural appetite regulation systems, helping to reduce hunger and support sustainable weight loss.

If you are considering Wegovy, it is important to understand how it works, what results to expect, and whether it is appropriate for your individual health needs. For a broader overview of weight loss medications, see our guide How Weight Loss Medications Work: A Medical Overview.

What is Wegovy and how does it work
Wegovy contains semaglutide, a medication that mimics the hormone GLP-1. This hormone is released naturally after eating and helps regulate appetite, slow stomach emptying, and signal fullness to the brain.

By enhancing these signals, Wegovy helps reduce appetite, increase feelings of fullness, and support better control over food intake. If you would like a more detailed explanation of GLP-1 medications, see our article What Are GLP-1 Medications and Why Do They Help With Weight Loss.

Who Wegovy may be suitable for
Wegovy is typically prescribed for adults with a higher body weight where lifestyle changes alone have not led to sustainable weight loss. In the UK, suitability is assessed based on factors such as BMI, medical history, and the presence of weight-related health conditions.

A clinical consultation is essential to ensure the treatment is appropriate and safe.

What to expect when starting Wegovy
Wegovy is taken as a weekly injection. Treatment begins at a low dose, which is gradually increased over time. This helps the body adjust and reduces the likelihood of side effects.

Many people notice changes in appetite within the first few weeks. Weight loss tends to develop gradually over several months rather than immediately. Progress varies between individuals and depends on factors such as consistency, lifestyle, and overall health.

Common side effects
Like all medications, Wegovy can cause side effects. The most common include nausea, vomiting, diarrhoea, constipation, and reduced appetite.

These effects are usually temporary and often improve as the body adjusts to treatment. Eating smaller meals and avoiding very rich or fatty foods can help manage symptoms. We explore this further in our upcoming guide to managing side effects of weight loss medication.

Wegovy compared to other medications
Wegovy works on the GLP-1 pathway, whereas other medications such as Mounjaro (tirzepatide) act on additional hormone pathways. Some people may respond differently depending on the medication used. We will explore this in more detail in our comparison article on Wegovy and Mounjaro.

Access and cost in the UK
Wegovy may be available through specialist NHS pathways or private providers. Access criteria and availability can vary, and private treatment typically involves ongoing clinical support and monitoring.

If you are considering private treatment, it is important to choose a regulated provider that offers appropriate medical assessment and follow-up care.

Medication as part of a wider plan
Wegovy works best when combined with changes in nutrition, physical activity, sleep, and stress management. Medication can make these changes more achievable, but it does not replace them.

For a complete overview of how medication fits into long term weight management, see our pillar guide Weight Loss Medication in the UK: A Patient-Centred Pillar Guide.

Further reading
• NICE guidance on obesity management
• NHS weight management services
• Clinical research on semaglutide