How effective is Wegovy for weight loss?

How Does Wegovy Work?

Wegovy is a once-weekly injectable prescription medicine that is designed to help adults who are overweight or obese lose weight when used alongside a healthy diet and regular physical activity.

Your body naturally produces a hormone called glucagon-like peptide-1 (GLP-1). GLP-1 helps control your appetite, how much you eat, and how your body handles sugar during digestion. Wegovy contains the active ingredient semaglutide (2.4 mg), which works in a similar way to GLP-1. It sends signals to your brain and gut that help reduce feelings of hunger and slow the rate of digestion.

How Does Wegovy Compare to Saxenda for Weight Loss?

Research from large 68-week clinical trials has shown that Wegovy can help many people lose a meaningful amount of weight when used alongside diet and physical activity. In one major study of adults with obesity (without diabetes) ², around 85% of people taking Wegovy lost at least 5% of their body weight over 68 weeks. People in the same study lost around 15% of their body weight on average, compared with about 2–3% in the placebo group ³.

In comparison, clinical studies of Saxenda showed that about two-thirds of people (around 60–70%) lost at least 5% of their body weight, with average weight loss of around 8–10%. This suggests that Wegovy may help more people achieve greater weight loss than Saxenda, although individual results still vary.

The longer-acting effect of Wegovy means it only needs to be taken once a week, which may make it easier to stay on treatment as prescribed. Saxenda is injected once daily; many people find this less convenient.

Both medicines can cause similar types of side effects, mainly affecting the stomach and gut. For more detailed information on possible side effects, see our comprehensive guide.

Ask your healthcare provider if Wegovy is right for you.

Wegovy® is used for weight loss and weight maintenance in addition to diet and physical activity in adults and adolescents aged 18 years and above who meet certain Body Mass Index (BMI) criteria. Wegovy® is also indicated to reduce the risk of a heart disease–related event in addition to standard of care if you are an adult with a history of heart disease and have a BMI ≥27 kg/m² without established diabetes. Wegovy® contains the active ingredient semaglutide and is available in the following dose forms: 0.25 mg, 0.5 mg, 1.0 mg, 1.7 mg and 2.4 mg. The two lower-dose pens contain 1.5 mL of liquid each, while the three higher-dose pens contain 3 mL each. Wegovy® has risks and benefits. Ask your healthcare provider if Wegovy® is right for you. Use strictly as directed. If you experience side effects, see your doctor, pharmacist, or healthcare professional. Side effects of Wegovy® include nausea, vomiting, diarrhoea, constipation, abdominal pain, headache, and fatigue. Please refer to the Wegovy® approved professional information available at: https://www.sahpra.org.za/registered-health-products/

Footnotes

• To be eligible for a Wegovy treatment programme, people need to have a BMI of 30 or more, or a BMI of 27 or more and at least one weight-related health condition, such as type 2 diabetes, high blood pressure, asthma, PCOS, erectile dysfunction, or high cholesterol.
• Wegovy’s cardiovascular indication is based on the SELECT trial, a large, randomised trial of semaglutide 2.4 mg once weekly in adults with overweight or obesity and established cardiovascular disease who did not have diabetes. Because the trial excluded people with diabetes, the label for this specific heart-disease indication also specifies “do not have diabetes.” This reflects the study design, not a universal rule that semaglutide cannot be used in people with diabetes.
• Based on the STEP 1 trial (*Once-Weekly Semaglutide in Adults with Overweight or Obesity*), a 68-week study of semaglutide 2.4 mg once weekly in adults with obesity or overweight (without diabetes), alongside diet and physical activity support.

Important safety information

Prescription medicine.