How Does Wegovy Work? The Science Behind Wegovy

If you’ve just started or are considering weight loss medication, but want to know more about how it works? Below, we unpack how it works, common side effects, and how to get started.

What is Wegovy?

Wegovy belongs to a class of medications called GLP-1 (glucagon-like peptide-1) receptor agonists, more commonly known as GLP-1s. It is a once-weekly injectable medication that contains the active ingredient semaglutide, which you may have heard of because it’s also the active ingredient in Ozempic. [1]

How does Wegovy aid in weight loss?

Wegovy (semaglutide) works by mimicking the naturally occurring GLP-1 hormone that’s released in your gut after you consume food. By mimicking this hormone, it’s able to aid in weight loss in a few different ways:

Appetite suppression

Wegovy activates receptors in the appetite control centre of your brain (called the hypothalamus) and your brainstem to reduce your appetite and increase feelings of fullness.

It also helps to reduce the desire to snack and stop “food noise”, an informal term which describes the feeling of constant food-focused thoughts, such as what to eat, when to eat, and how much to eat. It does this by reducing the rewarding effects of food in the brain. [1]

Slows digestion

Wegovy also slows down the rate at which food leaves your stomach (gastric emptying), helping you feel fuller for longer. [1]

Blood sugar regulation

After eating, Wegovy increases insulin secretion from your pancreas, which helps to control blood sugar levels and prevent sudden cravings. [1]

Results from Clinical Trials

The good news is that clinical studies show that Wegovy can lead to significant weight loss and important health benefits beyond the scale.

Weight Loss Results

In clinical trials, participants taking Wegovy lost an average of 15% of their body weight over two years when medication was used alongside a healthy diet and regular exercise. In this trial 77% of patients lost at least 5% of their starting weight, and 44% lost 10% or more. [2]

Other Health Outcomes

In a 40-month study involving people who were overweight or obese and had heart disease, weekly 2.4 mg doses of semaglutide significantly reduced the risk of major cardiovascular events:

• 18% lower risk of death from heart-related causes [3]
• 18% lower risk of non-fatal heart attacks [3]
• 18% lower risk of strokes [3]

Potential Side Effects of Wegovy

Like any medication, Wegovy can cause side effects, but these are usually mild and can be easily managed. Most people find they’re more likely to experience side effects temporarily when they start treatment or when their dose increases.

Common Side Effects

The most common side effects of Wegovy are gastrointestinal, which means they affect the digestive system. [4]

Common side effects include:

• Nausea
• Diarrhoea
• Vomiting
• Constipation

Serious Side Effects

Other, more serious side effects of Wegovy include increased heart rate and pancreatitis. While these are uncommon, it’s important to know the warning signs and seek medical attention if you notice anything unusual or concerning.

Pancreatitis 

Pancreatitis (inflammation of the pancreas) has been observed in clinical trials. Symptoms may include persistent, severe abdominal pain that can radiate to the back, sometimes accompanied by vomiting. If you think that you’re experiencing pancreatitis, stop treatment immediately and contact a healthcare provider. [1]

Increased Heart Rate

Increased resting heart rate has also been reported with Wegovy. Speak to your healthcare provider if you experience a racing heartbeat or heart palpitations while at rest. [1]

Anaphylaxis

Anaphylaxis and severe allergic reactions can be life-threatening. Symptoms may include difficulty breathing or swelling of the lips, tongue, or throat. If you experience any of these, stop treatment immediately and seek urgent medical attention. [1]

Acute Gallbladder Issues 

Acute gallbladder issues may cause severe pain under the right ribcage that can spread to the shoulder or back. This may be accompanied by vomiting, fever, or a rapid heartbeat. If these symptoms occur, stop treatment and contact a healthcare provider right away. [1]

Medical History Considerations

In safety studies, semaglutide has been linked to a possible risk of thyroid C-cell tumours. While this hasn’t been reported in any clinical studies. However, as a precaution, semaglutide should not be prescribed to individuals with a personal or family history of medullary thyroid carcinoma (MTC) or those with multiple endocrine neoplasia syndrome type 2 (MEN2). [1]

Ready to Start Your Weight Loss Journey?

If you’re ready to start your weight loss journey, the team at MedExpress can assess your eligibility and help you find a treatment that suits your lifestyle.

References

1. Wegovy 0.25 mg, FlexTouch solution for injection in pre-filled pen - Summary of Product Characteristics (SmPC) - (emc) [Internet]. www.medicines.org.uk. Available from: https://www.medicines.org.uk/emc/product/13799/smpc#gref
2. Garvey WT, Batterham RL, Bhatta M, Buscemi S, Christensen LN, Frias JP, et al. Two-year effects of semaglutide in adults with overweight or obesity: The STEP 5 trial. Nature Medicine. 2022 Oct 1;28(10):2083–91.
3. A. Michael Lincoff, Kirstine Brown‐Frandsen, Colhoun HM, Deanfield J, Emerson SS, Sille Esbjerg, et al. Semaglutide and Cardiovascular Outcomes in Obesity without Diabetes. The New England Journal of Medicine [Internet]. 2023 Nov 11;389(24). Available from: https://www.nejm.org/doi/10.1056/NEJMoa2307563
4. Wharton S, Calanna S, Davies M, Dicker D, Goldman B, Lingvay I, et al. Gastrointestinal tolerability of once‐weekly semaglutide 2.4 mg in adults with overweight or obesity, and the relationship between gastrointestinal adverse events and weight loss. Diabetes, Obesity and Metabolism. 2021 Oct 4;24(1).