Weight-loss medicine started to offer in South Korea.

 The weight-loss medication "Wegovy" is now available in South Korea. Developed by Novo Nordisk, Wegovy is administered as a once-weekly injection and has been officially approved as a treatment specifically for weight management.  It is designed to be used in combination with a reduced-calorie diet and increased physical activity. In other words, one should not expect obesity to be resolved by injections alone.

So how does Wegovy work?  

And how much weight loss can one realistically expect while using it? Also, what are the potential risks and financial costs users should be prepared to face? 

What is Wegovy?

Wegovy is the brand name for the drug semaglutide. Semaglutide is classified as a GLP-1 receptor agonist (GLP-1RA), which means it enhances the function of the GLP-1 (glucagon-like peptide-1) hormone naturally produced in the body. When we eat, the body normally secretes GLP-1, which sends signals to the brain to indicate fullness. Semaglutide amplifies this effect, creating a feeling of satiety—even without eating. GLP-1 also stimulates "insulin secretion", a hormone that lowers blood sugar (glucose) levels. Because of this function, semaglutide has been used for years as a treatment for type 2 diabetes.

Is Wegovy effective for weight loss?

As a semaglutide-based medication, Wegovy has strong scientific evidence supporting its effectiveness in promoting weight loss. It is also considered effective in maintaining weight loss, not just inducing it. According to recent studies, participants who followed the recommended usage of Wegovy over a four-year period lost on average 10.2% of their body weight and reduced their waist circumference by 7.7 cm.  In numbers, this translates roughly into "a 3-inch waist reduction". However, data also shows that when people stop taking the drug, approximately two-thirds of the lost weight tends to return —indicating that continued use is important for long-term results.

What are the side effects of Wegovy?

The most common side effects are nausea and vomiting. However, because Wegovy affects the entire body system, there is a possibility of more serious side effects. For instance, in animal studies, thyroid tumors and cancer were observed, although such cases are very rare in human studies.

4-Year Long-Term Clinical Trial Results

16.6% of Wegovy users (1,461 people) reported side effects serious enough to cause permanent discontinuation of the drug.  This is more than twice the rate seen in the placebo group (8.2%, or 718 people).

Types of side effects:

Gastrointestinal issues (nausea, vomiting) occurred in 10% of Wegovy users versus 2% of those on placebo.

Gallbladder-related disorders occurred in 2.8% of Wegovy users and 2.3% of the placebo group—just slightly above the margin of error.

Concerns about Suicidal Thoughts

As is the case with many hormone-modulating drugs, there is a potential risk for psychiatric effects. A recent global review of over 36 million reports of adverse events related to semaglutide-based drugs since 2000 identified 107 cases of suicidal thoughts or self-harm, including 6 actual deaths. Among users who discontinued Wegovy or its competitor Ozempic, 62.5% reported that suicidal thoughts subsided. However, it remains unclear whether factors like dosage, amount of weight loss, mental health history, or antidepressant use influenced these outcomes.

Impact on Social and Emotional Relationships with Food

Many people taking semaglutide drastically reduce their daily food intake.  As a result, they often skip meals or avoid social eating situations (e.g., gatherings, dining out). While this aligns with the drug’s purpose of inducing weight loss, it raises concerns about the potential erosion of emotional and social connections to food. Still, many in Korea might say that such trade-offs are worth it if it means losing weight—a perspective that may reflect cultural values around body image and self-discipline.

⚠️ The Catch: Rebound Weight Gain

The real issue, however, is what happens after you stop taking the medication. Studies show that about two-thirds of the lost weight tends to return when the treatment is discontinued.  This means Wegovy is not a short-term solution. To maintain weight loss, long-term prescription and consistent use are required. It’s a commitment—not a quick fix.