What is Wegovy: uses, dosage and more

Written by Rachel Honeyman 

Written by Rachel Honeyman 

last updated: Feb 21, 2023

9 min read

You’ve tried it all—cutting calories, exercising, maybe a fad diet or two (or three or four…)—but nothing seems to work for long-term weight loss. Your efforts might work for a few weeks or months, but inevitably, you wind up right back where you started. 

This frustrating cycle is familiar to anyone who’s struggled with their weight. Lest you think you’re alone, about one-third of US adults have obesity, at least half of whom are trying to lose weight at any given time. Within a year of losing weight, studies show 30–35% of that weight will be regained (Blomain, 2013). 

That’s where interventions like Wegovy for weight loss come in. Wegovy is a prescription medication that’s very effective at helping many people lose weight and keep it off. 

What is Wegovy?

Wegovy (also known by its generic name, semaglutide) is an injectable medication available through prescription only. It’s part of a class of drugs called GLP-1 receptor agonists. GLP-1 is a hormone that occurs naturally in your body and sends signals to your brain to help you regulate your food intake. Wegovy is FDA-approved for chronic weight management if you meet the following criteria (Novo Nordisk, 2022): 

  • Body mass index (BMI) of 30 or higher (classified as obesity)

  • BMI of 27 or higher (classified as overweight), along with a weight-related condition, such as diabetes, heart disease, or high blood pressure

Wegovy comes in a pre-filled injection pen. You inject it once a week subcutaneously (meaning, under the skin, as opposed to injecting it into a muscle). Subcutaneous injections are generally relatively painless, as the needle is tiny. 

Wegovy Important Safety Information: Read more about serious warnings and safety info.

Does Wegovy work?

Where diet and exercise alone might have failed you long-term, Wegovy could be the missing piece of the puzzle for you, as it is for many people. 

In one of the most significant clinical trials on Wegovy, participants who took Wegovy combined with lifestyle interventions (lowering food intake and increasing physical activity) lost an average of 15% of their body weight by the end of the 68-week trial. In comparison, the placebo group lost less than 2.5% of their body weight on average with just lifestyle interventions (Wilding, 2021). 

What’s most impressive is these results appear to have long-term effectiveness, as long as a person continues taking the drug. One study showed that, over the course of 68 weeks, those who continued taking Wegovy kept losing weight, while those who were switched to placebo at week 20 saw an average of 8% weight gain by the end of the trial (Rubino, 2021). 

That’s probably the biggest key, though. To see long-term results from Wegovy, you have to keep taking it. It works very well for most people, but if you stop taking it, you should expect to gain back the weight you lost. 

It helps to recognize that obesity and overweight are medical conditions, much like high blood pressure. A person with high blood pressure needs to keep taking their medicine to keep their blood pressure down—and the same idea applies to treating overweight and obesity with Wegovy. 

Weight loss

Fad diets stop here

If appropriate, get effective weight loss treatment prescribed for your body.

Fad diets stop here
Fad diets stop here

How does Wegovy help you lose weight?

As mentioned above, Wegovy is a type of drug called a GLP-1 receptor agonist—that stands for glucagon-like peptide-1 receptor agonist. That’s a mouthful of medical jargon, but here’s a simple way to understand how Wegovy works for weight loss:

Semaglutide—the active ingredient in Wegovy—mimics GLP-1, an appetite-regulating hormone we all have naturally in our bodies. The biggest difference between the GLP-1 produced by our bodies and semaglutide is how long it remains active. Natural GLP-1 kicks into gear after we eat, but only lasts about 2 minutes, while semaglutide remains active in the body for about 7 days (Lee, 2017; Rubino, 2022).

By ramping up the body’s levels of GLP-1, Wegovy does two main things (Hayes, 2011):

  • It keeps food in the stomach for longer, which helps you feel full for longer, reducing your overall appetite. 

  • It sends signals to the brain letting it know you’re satiated, which helps regulate your appetite. 

So, Wegovy works on both the body and the brain levels, which covers many of the bases involved in appetite regulation. 

What makes you hungry?

When you feel hungry, that’s not just a function of how much food is in your belly. You know this intuitively, as you’ve probably had the very common experience of downing a whole bag of chips, only to have a still-empty feeling in your stomach. 

That’s because appetite and hunger are really complicated! The brain communicates with a complex system of hormones, including ghrelin, leptin, and—you guessed it—GLP-1, which sends signals to the digestive system. Then, when you eat, as the food makes its way through your digestive system, signals are sent back to the brain to let it know you’re full (Parmar, 2022). 

Because this process is so complex, if any one of those steps along the way isn’t functioning properly, it can throw off your appetite and make you feel hungry even if your belly is technically full. 

Not to mention the fact that our environment plays a big role in our appetite and food cravings. 

Wegovy doesn’t affect every part of this complex system, but it does communicate with the part of the brain that controls appetite, and it slows down digestion, helping you stay full for longer. Together, these effects help you lose weight—and keep it off, as long as you’re taking the drug (Rubino, 2021).

Wegovy side effects

Since Wegovy impacts the way food passes through the digestive system, the main side effects are related to gastrointestinal complaints—namely, nausea, vomiting, and diarrhea. Still, most people tolerate Wegovy well; in trials, fewer than 7% of people stopped the medication because of side effects (Novo Nordisk, 2022). 

Here are some of the most common side effects you may experience with Wegovy (see the prescribing information for a full list of potential side effects) (Novo Nordisk, 2022): 

  • Nausea 

  • Vomiting

  • Diarrhea

  • Constipation

  • Abdominal pain

  • Headache

  • Fatigue

  • Indigestion

  • Dizziness

Not everyone should take Wegovy. If you have a history of the following health issues, let your healthcare provider know so they can recommend an alternative treatment option (Novo Nordisk, 2022): 

  • Medullary thyroid carcinoma (a type of thyroid tumor)—All GLP-1s, including Wegovy, come with a boxed warning (the most serious warning from the FDA) about their potential association with this type of cancer. While this effect has thus far only been seen in studies on rodents, it's unknown how high the risk is in humans. 

  • Pancreatitis 

  • Gallbladder disease

  • Low blood sugar (hypoglycemia)

  • Kidney failure

  • Diabetic retinopathy

  • Suicidal thoughts or behaviors

Wegovy may also increase heart rate, so your provider should monitor you for this risk. Stop Wegovy immediately if you have an allergic reaction to it. If you’re pregnant or planning to become pregnant, you should not take semaglutide, as there’s a chance it may cause harm to a fetus (Novo Nordisk, 2022).

If you or someone you know is experiencing thoughts or behaviors of suicide or self-harm, help is available for free. Contact the National Suicide Prevention Hotline.

National Suicide Prevention Hotline: 1-800-273-8255

Or text TALK to 741741 to text with a trained crisis counselor

Wegovy interactions

Wegovy has few drug interactions, and is safe to use alongside most medications. Because Wegovy lowers blood sugar levels, there’s an increased risk of hypoglycemia in people who are also on insulin or drugs that cause the body to secrete insulin. If you’re on insulin, you can likely take Wegovy, but you may require close monitoring.

If you’re taking any oral medications, your healthcare provider will likely want to monitor how Wegovy affects the way your body absorbs those other medications. Since Wegovy causes the stomach to empty more slowly, that can impact how the body absorbs oral drugs. 

Wegovy dosing

Wegovy comes in an injectable pen that’s prefilled with your prescribed dose. Your healthcare provider will likely start you at the lowest dose of 0.25 mg, which you’ll inject once a week for four weeks. If you tolerate that dose well, your provider will increase your dose, then continue increasing your dose every four weeks as tolerated until you reach the max dose of 2.4 mg (or the maximum dose you can tolerate) (Novo Nordisk, 2022). 

The typical dosing schedule is as follows (Novo Nordisk, 2022): 

  • Weeks 1–4: 0.25 mg injected once weekly

  • Weeks 5–8: 0.5 mg injected once weekly

  • Weeks 9–12: 1 mg injected once weekly

  • Weeks 13–16: 1.7 mg injected once weekly

  • Weeks 17 and beyond: 2.4 mg injected once weekly

Once you’ve reached the max dose, you’ll stay at a maintenance dose of 2.4 mg once a week (Novo Nordisk, 2022).

During the ramp-up period, your provider will decide how to increase or decrease your dose, depending on the weight loss results you’re seeing and how you’re tolerating possible side effects. The higher the dose you take, the more likely you are to experience side effects, so you may opt for a lower dose (and slower weight loss) if a higher dose causes too many adverse effects, or if a lower dose provides all the effectiveness you need. 

How to use Wegovy

When you fill your prescription for Wegovy, you’ll get a 4-week supply of four single-use pens that are prefilled with your prescribed dose. There’s a tiny, hidden needle at the tip of each pen, which is how you’ll inject yourself. 

You’ll use one pen a week, making sure to inject yourself on the same day each week. You don’t need to take Wegovy with food (though you can). 

It’s best to keep your injection pens in the refrigerator at 36–46ºF, but they’ll be safe to use if you keep them between 46–86ºF for up to 28 days.

Preparing your medication

  1. Wash your hands before picking up your Wegovy pen. 

  2. Make sure the new pen shows the correct prescribed medication and dose, and that it’s not past its expiration date. 

  3. Next, pull off the pen’s cap. 

  4. Through the pen window, look at the medication to make sure it’s clear and colorless. If it has any debris or particles in it, don’t use the medication; contact your pharmacy and your provider to see if you need a new pen. 

  5. Once you’ve determined the medication is clear, colorless, and particle-free, you can choose an injection site in either your stomach, thigh, or upper arm. Make sure to rotate exactly where you inject the medication each time, so you don’t cause irritation to the same area each week. 

Once you’ve selected an injection site, it’s time to administer your medication! 

How to inject Wegovy

  1. Clean the selected area on your abdomen, thigh, or upper arm with an alcohol wipe. 

  2. Hold the pen in one hand while you pinch the skin with the other hand. Then press the pen firmly against your skin and hold down the button. 

  3. You will hear a click when you start the injection, and the yellow bar on the pen should start moving. If the bar does not start moving, press the pen more firmly against the skin.

  4. Keep holding the button down for 10 seconds. You’ll hear a second click to let you know the injection is still going. Once you hear the second click, keep holding the button down until the yellow bar has stopped moving. 

  5. The yellow bar will stop moving right before the end of the window. Once the yellow bar has stopped, you can slowly remove the pen from your skin. Don’t remove the pen until the yellow bar has stopped moving.

  6. After you’ve administered the dose, dispose of the used pen in a sharps container (you can get one from your local pharmacy) or a heavy-duty plastic container with a screw-on lid. Because the semaglutide pen contains a needle, it’s important not to throw it into your regular trash. 

Wegovy cost

For anyone who’s experienced the struggle of weight loss, what we’ve shared so far about Wegovy may sound too good to be true. Well, there is one potential catch: the cost. The good news is it’s often covered by insurance, and there are ways to save if you have to pay out of pocket. 

The obvious best-case scenario is getting insurance coverage for Wegovy. You can find out if you have coverage by calling your insurance provider and asking if Wegovy (or another form of the active ingredient, semaglutide) is covered under your plan’s drug formulary.

In some cases, your healthcare provider’s office may have someone on staff who can help you navigate insurance coverage. With our Ro Body program, for instance, we include an insurance concierge service to help you get coverage. 

Without insurance, Wegovy costs around $1,500 per month on average, depending on which pharmacy you use. You can save several hundred dollars a month by using savings coupons from companies like GoodRx and SingleCare (GoodRx, 2022.; SingleCare, 2022).  

The manufacturer of Wegovy, Novo Nordisk, also offers a savings plan for eligible patients that can save you up to $500 per month (Wegovy, 2023). 

How to get Wegovy

If you meet the eligibility criteria for Wegovy, you can get this medication in a couple of ways. 

One option is to visit your primary care provider and discuss your options with them, or to find a physician who specializes in obesity medicine. 

Another convenient option is Ro Body, a 12-month program that includes: 

  • Your GLP-1 medication

  • Metabolic testing

  • A personalized treatment plan

  • 1:1 health coaching

  • A step-by-step curriculum

  • Ongoing support from your provider

  • A state-of-the-art smart scale

  • Insurance concierge services to help you get coverage

If you’ve struggled to lose weight sustainably with diet and exercise alone, adding Wegovy can be a great option to try. Studies show patients who do so lose an average of 15% of their bodyweight, and can keep that weight off as long as they stay on the drug. Speak with your healthcare provider to find out if it’s right for you.

Weight loss

Get access to GLP-1 medication (if prescribed) and 1:1 support to meet your weight goals

Wegovy alternatives

If the cost or side effects of Wegovy are prohibitive, you have other options available to you.

Wegovy is one of five medications on the market FDA-approved for weight loss (Khera, 2016):

  • Wegovy (semaglutide)

  • Saxenda (liraglutide)

  • Contrave (naltrexone/bupropion)

  • Alli and Xenical (orlistat)

  • Qsymia (phentermine/topiramate)

Of those, Wegovy and Saxenda are both GLP-1 medications. There are many other GLP-1 receptor agonists on the market, but most are only FDA-approved to treat type 2 diabetes, not weight loss. Some other examples of GLP-1 receptor agonists include:

  • Trulicity (dulaglutide)

  • Victoza (liraglutide)

  • Byetta (exenatide)

Semaglutide (the active ingredient in Wegovy) is also available under a different brand name, Ozempic, which is approved by the US Food and Drug Administration for managing type 2 diabetes. Some providers may prescribe Ozempic (and other GLP-1s) off-label as a weight loss medication.

Another new drug on the market, Mounjaro (tirzepatide), is a combination of a GLP-1 and GIP (another appetite-regulating hormone), that shows promise for weight loss (Jastreboff, 2022).

FAQs about Wegovy for weight loss

When thinking about starting any medication, it’s common to have questions about what to expect, and how to use it most effectively. Here are some of the most frequently asked questions you might have about taking Wegovy for weight loss:

Wegovy should be injected once a week on the same day of the week. If you miss a dose within 48 hours of your next dose, just skip your missed dose and resume your next dose at the planned time. If your next dose is scheduled in more than 48 hours, take the missed dose when you remember, then continue with your next scheduled dose. Speak with your healthcare provider if you miss two or more doses of Wegovy in a row, so you can set a new dosing schedule.
As long as you’re responding well to the medication and can tolerate any side effects, it’s recommended that you stay on Wegovy long-term. If you stop taking Wegovy, you’ll likely regain any weight you lost on it.
How long it takes to lose weight on Wegovy many vary person to person. Studies show it can take up to 20 weeks to see significant weight loss with Wegovy, with results continuing for at least 68 weeks (Wilding, 2021).
You can take Wegovy with or without food. The most important thing is to take it on the same day each week, preferably around the same time.
It’s best to keep your Wegovy pens in the refrigerator (between 36–46ºF), but you can keep them out of the fridge (between 46–86ºF) for up to 28 days.
Medicaid coverage for prescription drugs is state-specific, so you’ll need to contact your state’s Medicaid agency to find out if you can get coverage for Wegovy. Medicare doesn’t usually cover weight loss medications like Wegovy, but you can check your plan’s coverage for prescription medications.
Wegovy is injected with a tiny needle just under the skin in the abdomen, thigh, or upper arm. For most people, this doesn’t cause any pain. If it does cause any discomfort, that should fade within a few minutes.
There’s no specific diet you should be following while on Wegovy—no need to cut out any food groups. You’ll see the best results, though, with a reduced-calorie diet, and Wegovy can help with that. By making you feel fuller for longer, Wegovy can lower your appetite, making it easier to keep your calories in check.


If you have any medical questions or concerns, please talk to your healthcare provider. The articles on Health Guide are underpinned by peer-reviewed research and information drawn from medical societies and governmental agencies. However, they are not a substitute for professional medical advice, diagnosis, or treatment.

How we reviewed this article

Every article on Health Guide goes through rigorous fact-checking by our team of medical reviewers. Our reviewers are trained medical professionals who ensure each article contains the most up-to-date information, and that medical details have been correctly interpreted by the writer.

Current version

February 21, 2023

Written by

Rachel Honeyman

Fact checked by

Steve Silvestro, MD

About the medical reviewer

Dr. Steve Silvestro is a board-certified pediatrician and Associate Director, Clinical Content & Education at Ro.

Stay in touch on your weight loss journey

Sign up for news, updates, promotions and more.

By sharing your email, you acknowledge that your email will be used consistent with our privacy policy and terms of use including for marketing purposes.

    get video check ups with qualified medical advisors to review your progress on the Body Program

    $99 to get started, $145/mo for ongoing care

    What's included?

    Provider consultation

    GLP-1 prescription (if appropriate)

    Insurance concierge

    Ongoing care & support

    Tools to track progress

    Start now – $99

    Please note: The cost of medication and lab testing is not included in the Body Program

    Learn more about pricing

    Medication is prescribed only if appropriate.

    Get access to weight loss medications, if prescribed.

    Start now