How does semaglutide work for weight loss?

You will lose weight with semaglutide because you will eat less, and feel fuller when you do eat. Semaglutide does this by targeting an area in the brain (called GLP-1 receptors) that help to regulate your appetite and how much you eat. It closely mimics a natural hormone in the body called incretin, which is made primarily in our digestive tract.

Semaglutide is used as a long-term weight loss treatment in addition to a healthy diet and exercise to help promote weight loss. Semaglutide (Wegovy and Ozempic) are also approved to help protect the heart in patients with heart disease.

What is the mechanism of action of semaglutide?

Semaglutide is a glucagon-like peptide-1 (GLP-1) receptor agonist and occupies the GLP-1 receptor in the brain that regulates appetite.

It should not be used with other semaglutide-containing products (such as Ozempic, Rybelsus) or other GLP-1 receptor agonist medicines.

GLP-1 works by helps people to lose weight in 3 ways:

• It targets the brain centers that regulate appetite, especially after eating, which may help you eat less.
• It slows down how quickly the stomach empties, which makes you feel fuller for longer.
• Semaglutide treatment is recommended for long-term use if it’s effective for you. With continued use, semaglutide has been shown in studies to help people lose weight and keep it off for over one year.

Who can use semaglutide for weight loss?

Semaglutide for weight loss is approved to be used in adults and children 12 years of age and older based on their body mass index (BMI) and the presence of certain health conditions.

Semaglutide (Wegovy) is used in addition to diet and exercise for long-term weight management in:

• adults who are either obese (BMI ≥30 kg/m2) or overweight (BMI ≥27 kg/m2) with at least one weight-related condition such as high blood pressure, type 2 diabetes, or high cholesterol levels.
• adolescents 12 years and older with an initial BMI at or above the 95th percentile for age and sex (based on growth charts).
• Semaglutide (Wegovy) is also approved In adults, to reduce the risk of heart attack, stroke and heart-related death in people with cardiovascular (heart, blood vessel) disease with either obesity or overweight.

You can learn how to calculate an adult BMI here. Have your child's pediatrician determine their BMI percentile based on the current charts.

Other prescription drugs that also contain semaglutide are Ozempic (injection) or Rybelsus (oral tablets). These brands are only approved to treat type 2 diabetes, together with diet and exercise, and are not specifically approved for weight loss, but can lead to weight loss.

Semaglutide (Ozempic) is also approved to help protect the heart and lower the risk for heart attack, stroke or heart-related death in adults with type 2 diabetes and heart disease.

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How long does semaglutide take to work?

You may see some weight loss in the 4 weeks of semaglutide treatment, but the full effect can take several months. After 68 weeks, adults lost about 35 lbs (15.9 kg) in studies, on average.

Your doctor will slowly increase your dose when you start treatment to help lessen stomach side effects like nausea and diarrhea. It typically takes about 17 weeks to reach your final maintenance dose of semaglutide.

• Studies conducted by the manufacturer over 68 weeks show that, on average, adults using semaglutide lost about 35 lbs (15.9 kg), or about 15% of their body weight. In contrast, 31% of people using a placebo (inactive treatment) lost about 6 lbs (2.7 kg), or about 2.5% of their body weight.
• In children 12 years and older, semaglutide reduced their body mass index (BMI) by 16.1% after 68 weeks compared to a 0.6% reduction in the placebo group. Plus, the BMI was reduced by at least 5% in 77% of children receiving semaglutide compared to 20% receiving a placebo.

This is not all the information you need to know about semaglutide (Wegovy) for safe and effective use and does not take the place of your doctor’s directions. Review the full product information and discuss this information and any questions you have with your doctor or other health care provider.