Semaglutide is the active component of the weight-loss injection Wegovy and the type 2 diabetes drug Ozempic. Semaglutide for weight loss (Wegovy) is effective because it can increase feelings of fullness and reduce hunger. At the maintenance dose of 2.4 mg for 68 weeks, Wegovy (semaglutide) has been shown to help people lose up to 17% of their initial body weight.
Read on to learn about semaglutide, how it works, what to expect during treatment, and find answers to your frequently asked questions about this medication.
What Is Semaglutide?
Semaglutide is a glucagon-like peptide-1 (GLP-1) receptor agonist, a class of injectable and oral medications that help control blood sugar and reduce appetite by acting on receptors in the brain and gut to increase satiety, slow gastric emptying, and improve insulin response.
Semaglutide was first approved for the treatment of type 2 diabetes as Ozempic in 2017. A few years later, the FDA approved Rybelsus, a once-daily pill form of semaglutide.
As an added benefit, people with type 2 diabetes who take semaglutide usually lose weight. The company then studied the drug exclusively for weight loss, but at a higher dosage. As a result, Wegovy, the first once-weekly GLP-1 receptor agonist for weight loss, was approved in 2021.
In March 2024, the FDA expanded Wegovy’s label to include lowering the risk of serious cardiovascular events, including cardiovascular death, heart attack, and stroke, for adults with heart disease who have obesity or are overweight. Wegovy is the first weight-loss medication with that specific approval.
Wegovy is also approved to lower the risk of chronic kidney disease and to treat metabolic dysfunction-associated steatohepatitis (MASH), without cirrhosis of the liver.
Another form of semaglutide is compounded semaglutide. While it’s not approved by the FDA, it has the same active ingredient as the brand-name medications. Compounded semaglutide may be beneficial for people with special needs, such as those with allergies to certain ingredients.
Compounded medications may be prescribed when a person’s needs cannot be fulfilled by a commercially available medication or when there is a shortage.
How Does Semaglutide Work for Weight Loss?
Semaglutide is a GLP-1 receptor agonist and works by mimicking GLP-1, a natural hormone in your body that is released after eating. This hormone helps control your appetite, digestion, and the way your body responds to food. When you take semaglutide, it sends signals to the brain that help you feel full more quickly and for a longer period. This makes it easier to eat smaller portions without feeling deprived.
Semaglutide also slows the rate at which food leaves your stomach, which helps maintain steady hunger levels throughout the day. Many people notice they’re less interested in snacking or craving certain foods, especially sweets or salty snacks, because semaglutide reduces the brain’s reward response to those foods.
This medication also helps regulate blood sugar levels by enhancing insulin response after meals. All of these effects work together to lower your daily calorie intake and support consistent, long-term weight loss.
Semaglutide is most effective for weight loss when used alongside a healthy diet and regular exercise. Your healthcare provider can guide you on what foods and exercise routines to incorporate into your lifestyle.
How Effective Is Semaglutide for Weight Loss
Semaglutide has proven to be very effective for weight loss. In an early study, people who used semaglutide alongside a reduced-calorie diet and increased exercise were compared to those who made the same lifestyle changes without semaglutide. After 68 weeks, half of the people using semaglutide lost an average of 15% of their body weight, and nearly a third lost 20% or more.
People who made lifestyle changes alone experienced a 2.4% weight loss.
In a 2024 trial, semaglutide was administered for 4 years to 17,604 people with obesity, overweight, or cardiovascular disease. The findings demonstrated a significant reduction in waist circumference and weight loss that persisted throughout the four-year course.
The study also found that semaglutide was an effective weight-loss medication regardless of body size, sex, or geographic location.
Who Should Take Semaglutide for Weight Loss?
Semaglutide for weight loss is FDA-approved for chronic weight management in adults and adolescents aged 12 and older who meet specific body mass index (BMI) criteria and have no contraindications.
You may be a candidate for semaglutide if you meet one of the following criteria:
- You’re an adult with obesity (BMI of 30 kg/m² or higher).
- You’re an overweight adult (BMI of 27 kg/m² or higher) and have at least one weight-related condition, such as, high blood pressure, type 2 diabetes, high cholesterol, obstructive sleep apnea, and established cardiovascular disease.
- An adolescent aged 12 years and older with obesity (BMI in the 95th percentile or higher for their age and sex).
If you have tried lifestyle changes, such as diet and exercise, but still struggle to lose weight or maintain it, semaglutide may also be a good option for you. Because semaglutide works best as part of a comprehensive plan, your healthcare provider will prescribe it in conjunction with a healthy nutrition routine, regular physical activity, and routine follow-up.
Healthcare professionals also prescribe semaglutide off-label. If you don’t meet the above criteria, your provider may still prescribe it to you if they deem it necessary.
What Is the Semaglutide Dosage for Weight Loss?
Semaglutide dosage follows a process known as titration, meaning your dosage is slowly increased over time until you achieve an effective maintenance dosage.
The starting dose of semaglutide for weight loss is 0.25 mg once weekly. After that, your semaglutide doctor will guide you through the steps and advise you on when and how much to increase your dosage.
Your healthcare provider will typically increase your dosage every 4 weeks until you find a dosage that works for you while keeping side effects under control. The weekly maintenance dose of semaglutide for weight loss is 2.4 mg. However, if you can’t handle the 2.4 mg dose, you may be advised to inject 1.7 mg weekly as your maintenance dose. It may take several months to achieve your maintenance dose for semaglutide.
Here’s a quick look at the typical semaglutide dosing schedule for weight loss.
- Weeks 1-4: 0.25 mg once weekly
- Weeks 5-8: 0.5 mg once weekly
- Weeks 9-12: 1.0 mg once weekly
- Weeks 13-16: 1.7 mg once weekly
- Week 16 and beyond: Maintain at 1.7 mg or increase to 2.4 mg once weekly maintenance dose
This gradual increase helps minimize common side effects like nausea, bloating, or stomach discomfort.
Compounded semaglutide dosage is the same as that of branded semaglutide (Wegovy). However, your healthcare provider may recommend a customized dosing schedule tailored to your individual needs.
Where to Inject Semaglutide for Weight Loss
Semaglutide for weight loss is injected once weekly into the fatty (subcutaneous) layer just under the skin.
This involves inserting a very thin needle into the fatty tissue layer directly beneath the skin.
Wegovy is available as a single-use injectable pen. The needle has been attached to the pen, and your dosage has already been predetermined. You will discard each pen after use because it contains only one dose.
Compounded semaglutide comes in a small vial, from which you’ll measure your weekly dose using a single-use syringe.
When you’re prescribed semaglutide for weight loss, a healthcare provider will guide you on how to inject the medication. They will also advise you on the dosage of semaglutide.
The best injection sites include the abdomen, thighs, and upper arms. If you find the abdomen as the easiest and best site, it’s important to avoid the 2-inch area around the belly button.
Rotate your injection site weekly to minimize irritation, bruising, and tenderness.
Whether you choose your stomach, thigh, or arm, the medication works the same as long as it’s injected correctly into fatty tissue.
Semaglutide vs. Tirzepatide: How Do They Compare?
Tirzepatide is a once-weekly injectable drug available in two brand names: Mounjaro and Zepbound. Like Ozempic, Mounjaro is FDA-approved for the treatment of type 2 diabetes in adults, while Zepbound is approved for chronic weight management and obstructive sleep apnea (OSA) in some adults.
While both semaglutide and tirzepatide are injectable medications used for weight loss, they work in slightly different ways and can lead to different results. Semaglutide is a GLP-1 receptor agonist, while tirzepatide is a dual GIP and GLP-1 receptor agonist. This dual action means tirzepatide may enhance insulin response and appetite suppression even more than semaglutide in some people.
When it comes to effectiveness, clinical studies suggest that both medications produce significant weight loss, but tirzepatide often shows slightly higher average weight reductions. For example, in head-to-head trials, individuals on tirzepatide lost 20–22% of their body weight over 72 weeks, whereas those using semaglutide typically lost 15–17% during a similar period.
Side effects are similar for both drugs, with the most common being gastrointestinal issues such as nausea, vomiting, and diarrhea. Because of its dual mechanism, some patients report slightly more pronounced nausea with tirzepatide, especially during dose escalation.
In terms of dosing, semaglutide reaches a maintenance dose of 2.4 mg weekly, while tirzepatide is titrated up to 15 mg weekly. Both require gradual titration to improve tolerance and minimize side effects.
Choosing between the two depends on individual factors, such as medical history, weight-loss goals, tolerance for side effects, insurance coverage, and cost. Your healthcare provider can help you determine which option is safest and most effective for you.
What Is the Cost of Semaglutide for Weight Loss?
The cost of semaglutide for weight loss varies depending on whether you have insurance, which dose you’re using, and where you buy it. The full retail price for a 28-day supply of Wegovy is about $1,349.
In early 2025, Novo Nordisk introduced a direct-to-consumer option via their NovoCare pharmacy, where people without insurance can pay $499 per month for Wegovy. Costco is also selling Wegovy at the same price.
Compounded semaglutide is less expensive than brand-name medications. For example, when you obtain compounded semaglutide through NP2GO, the price starts at $199/month.
Insurance rarely covers semaglutide when it’s prescribed specifically for weight loss. Coverage is far more likely if you’re using it to manage type 2 diabetes, since insurers view that as a medical necessity rather than an elective treatment.
Even when a plan does include semaglutide for weight management, there are often several steps involved. Your healthcare provider may be required to submit a prior authorization, and approval usually depends on meeting certain requirements, such as having a BMI within a qualifying range or documenting previous attempts at weight loss.
What Are the Side Effects of Semaglutide Injections?
Semaglutide is effective for weight loss, but like most medications, it can cause side effects, especially when you’re starting treatment or increasing your dose. Most reactions are mild and improve as your body adjusts.
Common semaglutide side effects
Many people experience stomach-related symptoms when they first begin semaglutide. These often include
- Nausea
- Bloating
- Gas
- mild stomach discomfort
- Vomiting
- Constipation
- Diarrhea
- reduced appetite
- Headaches
- Tiredness
- Injection-site redness
Serious semaglutide side effects
While rare, semaglutide may cause serious side effects, which may include:
- Pancreatitis
- Gallbladder problems
- Severe stomach pain
- Allergic reaction
- Difficulty breathing
- Vision changes
- Kidney concerns
The FDA also includes a boxed warning for a potential increased risk of thyroid C-cell tumors. These tumors were seen in animal studies, but there have been no confirmed reports of thyroid C-cell tumors in humans taking semaglutide. Even so, anyone with a personal or family history of medullary thyroid carcinoma (MTC) or MEN 2 should avoid this medication.
Tips for managing stomach side effects
Most stomach issues can be managed with simple changes. Eating more slowly, choosing smaller portions, and avoiding heavy, greasy, or spicy foods can help ease discomfort. Staying hydrated, focusing on bland foods when you feel nauseous, and avoiding alcohol can also support your digestion. Symptoms often improve during each step of the dose-titration schedule, so following your provider’s instructions closely is important.
What if I Skip a Week of Wegovy?
If you skip a week of Wegovy and your next scheduled dose is more than 48 hours away, take the missed dose as soon as you remember. However, if your next injection is less than 48 hours away, skip the missed dose and take the next one on your regular day.
If you’ve missed two or more weekly doses, contact your healthcare provider before injecting again. They may advise resuming your usual schedule or recommend restarting at a lower dose to help minimize side effects and safely get you back on track.
Because semaglutide is taken weekly, remembering your injection can take a little planning. These simple habits can help reduce the chances of missing a dose:
- Set a phone reminder or calendar alert.
- Write your injection day on a planner, calendar, or sticky note you see often.
- Pair your dose with a weekly routine you never skip, like weekly grocery shopping, a standing meeting, or a regular chore.
FAQs About Semaglutide for Weight Loss
How long does it take for semaglutide to start working for weight loss?
You may start to notice a reduced appetite within the first few weeks, but the full effect builds over several months as the dose increases. Significant results may appear between 8–12 weeks, with continued progress as you reach your maintenance dose. Stay consistent with dosing and healthy habits to maximize your results.
Will I regain weight if I stop semaglutide?
You may regain weight after stopping semaglutide, especially if you’re not committed to lifestyle changes like diet and exercise. This is because your appetite and digestion return to normal. Studies show many people regain a significant portion of the lost weight, sometimes regaining up to two-thirds of it within a year. To maintain progress, continue to adopt strong lifestyle habits and work with a provider to guide you on nutrition, physical activity, and long-term strategies.
Is semaglutide the same as Ozempic or Wegovy?
Semaglutide is the active ingredient in both Ozempic and Wegovy. Ozempic is approved for type 2 diabetes and sometimes used off-label for weight loss, while Wegovy is FDA-approved specifically for chronic weight management. The medications contain the same drug but are approved for different purposes and use different dosing schedules.
Can I drink alcohol on semaglutide?
You can drink alcohol while taking semaglutide, but it’s best to do so cautiously. Alcohol can worsen nausea or digestive side effects and may affect blood sugar levels, especially for people with diabetes. Limiting intake and avoiding heavy drinking can help prevent discomfort and support safer, more effective treatment.
Is semaglutide safe for people with diabetes?
Yes, semaglutide is prescribed for people with type 2 diabetes because it helps manage blood sugar and supports weight loss. However, it may increase the risk of low blood sugar when taken with other diabetes medications. Tell your healthcare provider if you’re using other diabetes medications, so they may adjust your treatment plan and monitor your levels to keep you safe.
Start Your Journey with Semaglutide for Weight Loss with Confidence
Semaglutide for weight loss is a GLP-1 receptor agonist that has proven effective in helping people lose weight. If you’ve struggled to lose weight and keep it off with diet and exercise alone, speak to a provider in NP2GO to help you see if this treatment is right for you. We provide expert guidance, transparent pricing, and compassionate care. Schedule your consultation today and take the first step toward a healthier, more confident you.