Semaglutide for Weight Loss: 09 Facts On How It Works and How It’s Changing Treatment in Europe

In recent years, semaglutide — a once-weekly injectable medication originally developed for Type 2 diabetes — has rapidly evolved into one of the most talked-about solutions for obesity treatment. Known by its brand names Wegovy, Ozempic, and Rybelsus, this glucagon-like peptide-1 (GLP-1) receptor agonist is not only reshaping the weight-loss market in the United States, but also gaining traction across Europe, where obesity rates continue to climb and healthcare systems are grappling with the economic and clinical toll of chronic metabolic disease.

As more European countries approve semaglutide for obesity management, and as public demand soars, it’s worth examining how this treatment works, who it’s for, and how it compares to other available therapies on the continent.

What Is Semaglutide?

Semaglutide is a synthetic version of GLP-1, a naturally occurring hormone that helps regulate appetite, blood sugar, and insulin secretion. It was first approved in 2017 in the EU under the brand Ozempic for Type 2 diabetes, followed by Rybelsus, an oral tablet version. But its benefits quickly became apparent beyond blood glucose control: patients also began experiencing substantial weight loss.

This led to targeted studies at higher doses, culminating in the approval of Wegovy in the US (2021) and the European Medicines Agency (EMA) recommending its approval for chronic weight management in 2022. Countries such as Germany, Denmark, the UK, and the Netherlands have since adopted it — with others following suit.

How Semaglutide Works for Weight Loss

Semaglutide promotes weight loss in three key ways:

1. Delayed Gastric Emptying: It slows down how quickly food leaves your stomach, helping you feel fuller for longer.
2. Appetite Suppression: It targets the brain’s appetite control centers, reducing hunger signals.
3. Craving Control: It diminishes desire for high-calorie foods, such as sweets or salty snacks.

These effects often result in patients naturally reducing calorie intake, even without strict dieting. However, sustained weight loss depends on continuous use, as the benefits begin to reverse once the drug is discontinued.

How Effective Is Semaglutide?

In clinical trials such as STEP 1 and STEP TEENS, semaglutide led to an average weight loss of 15% to 18% of starting body weight — a dramatic improvement over older therapies.

To put this into perspective:

The superiority of semaglutide over older oral weight-loss medications has led to overwhelming demand, even causing shortages across pharmacies in the UK and parts of the EU in 2023 and 2024.

Who Should Take It?

In Europe, Wegovy is typically prescribed for:

• Adults with a BMI ≥30 (classified as obese), or
• Adults with a BMI ≥27 who also have a weight-related health condition (e.g., high blood pressure, Type 2 diabetes, or dyslipidemia)

Some countries, such as the UK under the NHS, have placed tighter controls on access, limiting semaglutide to specialist weight-management services to ensure it is used judiciously and not for cosmetic purposes.

How to Use Semaglutide

Wegovy comes in a pre-filled single-use pen that is injected once weekly, subcutaneously into the abdomen, thigh, or upper arm. The dosing schedule typically ramps up over 16 weeks:

• Start at 0.25 mg per week
• Gradually increase to 2.4 mg per week, the maintenance dose

This titration helps manage side effects, especially gastrointestinal issues like:

• Nausea
• Vomiting
• Constipation
• Diarrhea
• Abdominal pain

Less common but serious risks include pancreatitis, gallbladder disease, and in rare cases, thyroid C-cell tumors (not yet observed in humans, but found in animal studies).

How Does It Compare to Tirzepatide?

While semaglutide has revolutionized weight-loss care, it may soon face competition from tirzepatide (brand name Zepbound in the US, not yet approved in the EU as of mid-2025).

Tirzepatide mimics two hormones — GLP-1 and GIP — and has shown even greater weight-loss effects in trials (up to 20% body weight loss). However, it lacks cardiovascular approval in Europe and is still under EMA review.

Semaglutide in the Context of European Healthcare

One of the unique challenges in Europe is balancing individual care with public health systems. In countries with socialised medicine like the UK (NHS) or Scandinavia, questions remain around:

• Who pays for semaglutide?
• How long can it be prescribed?
• Will long-term use be cost-effective?

In Germany, semaglutide may be covered by insurance if medically justified, while in France, it’s available under hospital prescription with strict inclusion criteria. Denmark, home to manufacturer Novo Nordisk, has among the highest uptake, in part due to early local access and favorable reimbursement.

Long-Term Considerations: Not a Magic Wand

While semaglutide is a powerful tool, it isn’t a substitute for healthy lifestyle changes. Rebound weight gain is common if therapy is stopped, and semaglutide is not a one-time cure — it’s a long-term medical strategy, much like statins for cholesterol.

There are also ethical concerns in Europe around off-label use, especially when drugs intended for patients with chronic health needs are diverted for aesthetic or celebrity-driven weight loss.

The Future of Semaglutide in Europe

As of 2025, semaglutide’s momentum continues across Europe, with:

• New indications likely (e.g., prediabetes, addiction treatment)
• Broader use in cardiometabolic protection
• Ongoing research into oral versions with weight-loss doses

Novo Nordisk is also scaling production to meet global demand, aiming to resolve the shortages that plagued 2023 and 2024.

Final Thoughts

Semaglutide (Wegovy) has reshaped the weight-loss landscape in Europe, offering real hope for patients struggling with obesity and its complications. Its success reflects a growing recognition of obesity as a medical condition, not a failure of willpower. But it’s not without trade-offs — side effects, cost, and long-term dependency must be factored into any decision.

Before starting semaglutide, talk to your GP, endocrinologist, or obesity specialist. In many EU countries, access still requires a formal evaluation and prescription, often through a multidisciplinary weight-management team.

In the coming years, semaglutide may become a standard of care, not just a breakthrough. But its integration into European healthcare systems must be careful, ethical, and evidence-based — ensuring the benefits outweigh the hype.