What to know about semaglutide weight loss

In this article:

• What is semaglutide?
• Semaglutide for weight loss
• How long does it take to work?
• Efficacy
• Side effects
• How to get semaglutide

In this article

• What is semaglutide?
• Semaglutide for weight loss
• How long does it take to work?
• Efficacy
• Side effects
• How to get semaglutide

Weight loss pills have long been popular. More recently, there has been an unprecedented focus on new weight loss drugs with the same active ingredient: semaglutide. This glucagon-like peptide-1 (GLP-1) receptor agonist is the active ingredient in Wegovy, Rybelsus, and Ozempic—the last of which has become a household name after countless celebrities spread the word that it helped them lose weight. 

Keep reading to learn about semaglutide weight loss, how it works, and how to get it.

What is semaglutide?

Semaglutide belongs to a class of drugs called GLP-1 receptor agonists. The U.S. Food and Drug Administration has approved drugs containing semaglutide to treat Type 2 diabetes and promote weight loss and weight management. Some are also approved to help lower the risk of heart disease and cardiovascular events in people with diabetes or obesity.

Semaglutide is available in oral and injection form. It is the active ingredient in the brand-name, FDA-approved drugs Ozempic, Wegovy, and Rybelsus. Novo Nordisk is the only pharmaceutical company that makes FDA-approved medications containing semaglutide. However, the popularity of these medications has led to drug shortages, so some pharmacies make custom-made versions of semaglutide called compounded semaglutide, which are not FDA-approved.

How does semaglutide work for weight loss?

Semaglutide medications were initially intended to treat diabetes. That’s because semaglutide, like other GLP-1 inhibitors, helps the pancreas release insulin to process glucose when blood sugar levels are too high. However, the SUSTAIN clinical trials of Ozempic (semaglutide) showed that in addition to blood sugar control, the drug caused weight loss in participants with Type 2 diabetes and obesity. 

“Semaglutide acts on the brain to suppress appetite,” explains Daniel Kim, DO, a board-certified family physician with Medical Offices of Manhattan and LabFinder contributor. “It increases the feeling of ‘fullness’ and reduces hunger signals by binding to GLP-1 receptors in the brain.” But semaglutide doesn’t only combat cravings. Dr. Kim says it also physically “slows down stomach emptying,” which makes people feel full for longer. 

The bottom line: When a person’s appetite is suppressed and they feel full for longer after eating, they eat less. By eating fewer calories, people on semaglutide lose weight. 

How long does it take to work?

Oral semaglutide is taken once daily, while subcutaneous injections are administered weekly. In both forms, semaglutide starts working immediately, but results don’t happen overnight. It can take weeks or even months to notice body weight changes, and the rate of weight loss is different for each person. 

In one study of semaglutide injections for weight loss, participants lost an average of 5.9% of their total body weight in three months and an average of 10.9% in six months. 

No matter what form of semaglutide is prescribed, people start on the lowest dose to help the body adjust to the medication. Not everyone experiences noticeable changes in body weight while on the lowest dose. That’s normal and not a reason to rush to a higher dose. Regardless of dosage, it takes time for the medication to reach a steady state in the body. Ozempic and Wegovy dosage can be increased after four weeks on the starting dose. Rybelsus dosage can be increased after 30 days on the starting dose. 

It’s important to understand that semaglutide only works for chronic weight management when taken continuously as prescribed. Quitting semaglutide could result in weight gain. Research is ongoing, but current studies suggest that semaglutide users who quit taking semaglutide regain an average of two-thirds of the weight lost within the first year of quitting.

Bottom line: Semaglutide is not a magic bullet for rapid weight loss. It promotes long-term weight loss, and research suggests that ongoing treatment is required to maintain the reduced body weight.

Efficacy for weight loss

Semaglutide is very effective for weight loss (and managing blood sugar levels), but how much body weight a person loses—and how fast—depends on dosage and lifestyle choices.

In a larger double-blind clinical trial, participants on once-weekly semaglutide injections lost an average of 15% of their baseline body weight over 68 weeks. For example, on average, a 200-pound person lost around 30 pounds after 15 months. Weight loss does not always occur steadily, so it’s possible that a participant could lose 20 pounds within a few months and then the next 10 pounds more slowly. But again, results vary from person to person. Some research shows that people can lose an average of 5 pounds monthly on semaglutide.

It is possible to speed up weight loss on semaglutide by switching to a higher dose or implementing a healthy diet and physical activity. Ultimately, lifestyle changes are necessary to achieve the most significant weight loss and to maintain good long-term health. People who want to optimize their results on semaglutide must understand that a long-term commitment to a healthy diet and exercise is required.

“You can improve effectiveness and speed of weight loss on semaglutide with lifestyle changes such as reduced caloric intake, avoiding processed foods and sugars, and increasing aerobic exercises and strength training,” says Dr. Kim. He adds that staying well-hydrated throughout the day and getting at least seven hours of sleep per night can also improve the odds of effective weight loss.

Semaglutide side effects 

The most common side effects of semaglutide include:

• Nausea
• Vomiting
• Stomach pain
• Diarrhea
• Constipation 
• Gassiness (flatulence)

Less commonly, semaglutide can cause serious side effects such as life-threatening allergic reactions, kidney problems, gallstones, pancreatitis, or gallbladder inflammation. It’s important to talk to your prescriber about potential adverse events before taking and while using semaglutide. 

How to prevent common side effects

Many healthcare providers recommend staying hydrated and eating smaller portions to minimize the risk of nausea and gastrointestinal issues from semaglutide. It’s normal to feel full quickly, so eating smaller portions more frequently may help a person get essential nutrients without triggering side effects. Because appetite is suppressed, food consumption is down, making food quality more important than ever. Prioritizing protein-rich foods like lean meats, legumes, and whole grains can help maintain muscle mass while losing weight. Sipping water or electrolyte drinks throughout the day can also stave off nausea and constipation. 

How to get semaglutide

First, you must ask a prescribing health care professional for a semaglutide product prescription. 

In getting a prescription, discussing the benefits and drawbacks of oral versus injectable semaglutide is important. While some patients prefer the convenience of oral medicine, “the efficacy is better with the injectables, and the need to take them is less frequent,” says Inna Melamed, Pharm.D., a functional medicine practitioner and author of Digestive Reset.

In addition to the form of medication, there are costs to consider. Generic semaglutide doesn’t exist yet, so people have two options: Brand-name semaglutide or compounded semaglutide.

• Ozempic: Semaglutide sold under the brand name Ozempic is an FDA-approved subcutaneous injection for diabetes management, though it is sometimes prescribed off-label for weight loss. Typically, Ozempic is prescribed for weight loss to people with Type 2 diabetes or certain other health conditions associated with obesity.
• Wegovy: Semaglutide sold under the brand name Wegovy is an FDA-approved subcutaneous injection for weight loss in individuals with a body mass index (BMI) of 30 or higher or a BMI of 27 or higher with at least one weight-related health condition.

• Rybelsus: Semaglutide, sold under the brand name Rybelsus, is an FDA-approved oral medication for diabetes management. Like Ozempic, Rybelsus is sometimes prescribed off-label for weight loss.

• Compounded semaglutide: Compounded versions of semaglutide are not FDA-approved but are currently legal and made by licensed pharmacists. Compounded medications have not undergone the same rigorous testing as FDA-approved medications and may vary in their content. There is also a greater risk of incorrect dosing. (Novo Nordisk, the drug manufacturer of brand-name semaglutide products, has asked the FDA to ban compounded semaglutide.) Dr. Melamed says anyone considering compounded semaglutide should look for accredited pharmacies on the Alliance for Pharmacy Compounding website. “Call and ask [the pharmacy] questions, including if they are accredited,” she says. 

Many people on semaglutide for weight loss wonder if saving money on their prescriptions is possible. The answer is yes. One way to save on semaglutide is with a free SingleCare discount card, which offers prescription discounts of up to 80%.

Novo Nordisk also has a discount card that can help eligible insured patients get Ozempic for as little as $25 per month. However, there are eligibility requirements.