What you’ll learn:
- Wegovy is a once-weekly injectable medication containing semaglutide, which is FDA-approved to help people lose weight.
- Common side effects, which include nausea, diarrhea, and stomach discomfort, are manageable and often ease as your body adjusts to the medication.
- While serious side effects are rare, it’s important to understand the risks and work closely with your healthcare provider.
Wegovy® has become one of the most talked-about tools for weight loss because it can be very effective. This once-weekly medication helps quiet hunger cues and supports long-term weight management by working with your body’s natural appetite signals. If it sounds familiar, that’s because it shares the same active ingredient (semaglutide) as Ozempic®—the diabetes medication that’s gained attention for its off-label use in weight loss.
Wegovy® was officially approved by the FDA in 2021 for weight management, making it the first new prescription drug in years to receive approval for this use. Since then, it has become a go-to option for many people who have struggled to lose weight through lifestyle changes alone.
But while Wegovy® has been a helpful tool for many, it’s not without its challenges. It often comes with side effects. Most are common and manageable with diet and lifestyle changes.. There’s one in particular that tends to show up early on. Others may be more serious and require medical attention—they’re important to be aware of before you start the medication..
We’ll walk through what to expect, how to manage side effects, and how to feel more confident and supported throughout your Wegovy® experience.
How Wegovy® and semaglutide work
The semaglutide in Wegovy® works by mimicking a hormone your body already makes called GLP-1 (glucagon-like peptide-1). GLP-1 is naturally released after eating and other activities, like exercise. It plays a major role in managing hunger, blood sugar levels, and digestion. When you take Wegovy®, you’re activating the receptors that respond to GLP-1, giving those processes a boost.
Wegovy® acts on the brain’s appetite centers to reduce hunger and encourage satiety. It also helps slow down how quickly food leaves your stomach, keeping you full longer. These changes can lead to a natural decrease in calorie intake, helping you make better diet choices.
On the metabolic side, Wegovy® helps your body manage blood sugar more efficiently. It tells your pancreas to release insulin when you eat and reduces the release of glucagon, a hormone that raises blood sugar. This supports better glucose control and may help lower the risk of blood sugar spikes after meals.
Wegovy® starts at a low dose and gradually increases every month or every few months at the discretion of your doctor—a process designed to help your body adjust and reduce the risk of side effects. It’s taken once a week as an injection under the skin with a prefilled pen, in the stomach, thigh, or upper arm. Everyone begins with the lowest dose ( 0.25 mg weekly), then steps up in dose as tolerated to keep losing steady weight.
Common side effects of Wegovy®
When first starting Wegovy®, most people start to notice changes within the first few weeks, both in how their body reacts to the medication and in how their appetite shifts. It can take several weeks before the full effects of that particular dose are reached. Many side effects show up during this adjustment period.
Here’s what you might experience, based on clinical trials, and some tips on how to handle them.
Gastrointestinal symptoms
Digestive issues are the most common side effects people notice when starting Wegovy® and when the dose is increased. While these symptoms can be uncomfortable, most tend to improve over time as your body adjusts.
Here’s a breakdown of the most frequently reported gastrointestinal symptoms from clinical trials and some tips on how to handle them:
| Symptom | % reported | Why it happens | What can help |
|---|---|---|---|
| Nausea | 44% | Wegovy® makes your stomach empty more slowly and changes how your digestive hormones work. | Eat small, low-fat meals as recommended by Novo Nordisk, and steer clear of greasy or very spicy foods, which is a standard approach for managing nausea. |
| Vomiting | 24% | Happens when nausea gets severe and because Wegovy® affects how your stomach muscles move. | Sip clear fluids or eat bland foods like rice or applesauce—this is a common approach that tends to work well when you’re feeling queasy. |
| Diarrhea | 30% | Wegovy® changes how quickly food moves through your digestive system and affects your digestive juices. | Healthcare experts recommend staying hydrated and trying a low-fiber diet to give your digestive system a break when diarrhea hits. |
| Constipation | 24% | When your stomach empties more slowly, everything else slows down too. | Doctors often suggest gradual fiber intake, drinking more water, and daily movement to help get digestion moving again. |
| Stomach pain/discomfort (abdominal pain) | 20% | Your digestive muscles may cramp as your body adjusts to the medication. | Sipping clear fluids and avoiding solid food for a few hours is a usual go-to when your stomach feels off after eating. |
| Indigestion/heartburn | 9%/5% | Wegovy® can change your stomach acid levels and relax the muscle that keeps acid from going up into your throat. | Eating slowly and avoiding lying down right after meals are common tips that can ease the burn of indigestion. |
Still feeling off a few weeks in? Your provider can help you figure out what’s going on and if a change might help. For day-to-day support, Noom’s GLP-1 Companion offers personalized tools to help you manage side effects, build habits, and stay focused on your goals. With tailored guidance and a dedicated support team, it’s designed to help you make the most of your medication for the long term.
Other symptoms
Wegovy® can also cause general changes in your overall well-being. These neurological symptoms are usually mild and temporary, but still important to watch for:
| Symptom | % reported | Why it happens | What can help |
|---|---|---|---|
| Headache | 14% | Headaches can be caused by dehydration (from vomiting or diarrhea) or your body adjusting to hormonal changes from the medication. | Healthcare experts suggest drinking more water and taking screen breaks as simple ways to ease early headaches. |
| Fatigue | 11% | Eating less and dehydration from side effects can make you tired. Fatigue may also be due to how Wegovy® changes metabolism and how your body uses energy. | Getting enough rest and eating balanced meals is a common go-to for managing fatigue. Light activity is also encouraged by healthcare experts to help restore energy. |
| Dizziness | 8% | Wegovy® can cause dizziness by lowering blood sugar levels, changing blood pressure, and through dehydration from digestive side effects. | A common tip is to avoid quick movements and stay hydrated—shifting positions too fast can worsen dizziness. |
Some people also report other experiences that aren’t listed in official clinical trial data but are frequently discussed in real-world settings. Here is what one study found:
- Sleep disturbances or insomnia: Difficulty falling asleep or staying asleep has come up frequently in online discussions. These issues may be related to how your body adjusts to semaglutide.
- Mood changes or anxiety: While not officially documented in trials, some people have reported increased anxiety, low mood, or emotional changes. The cause isn’t fully clear, but it’s something to watch for.
Most of these symptoms improve with time, especially if you’re easing into your dose increases gradually. If anything starts to interfere with your daily routine, it’s a good idea to reach out to your healthcare provider for support.
Wegovy®: Injection site reactions
While the Wegovy® pen is designed to be easy to use and relatively painless, mild skin reactions are still common at the injection site. Here’s what you might experience:
- Redness or swelling – You might see a small red or raised area at the injection site, especially in the hours after your shot. This is generally temporary and should fade within a day or two.
- Itching or irritation – Mild itching is also possible, and while it can be uncomfortable, it usually doesn’t last long. Avoid scratching the area to reduce irritation.
- Tenderness or bruising – Some people experience mild pain or a small bruise after injection. This is often related to the placement of the needle.
To reduce the likelihood of injection site issues:
- Rotate injection sites each week (abdomen, thigh, or upper arm). Keep a chart!
- Always clean the skin with an alcohol swab and allow it to dry before injection.
- Inject slowly and avoid rubbing the area afterward.
If you notice persistent redness, pain, or signs of infection like warmth or pus, check in with your healthcare provider. Otherwise, these reactions are usually mild and manageable with a few simple adjustments.
Metabolic and cardiovascular symptoms
Some people taking Wegovy® experience side effects related to blood sugar levels and heart rate. These may show up early in treatment or as your dosage increases, and it’s important to monitor how your body responds.
- Shakiness, fatigue, dizziness, or confusion may signal drops in blood sugar. While more common in people also taking insulin or sulfonylureas, these symptoms can still occur and shouldn’t be ignored.
- Rapid or pounding heartbeat has been reported by some people, sometimes without any obvious trigger. Clinical trials found that Wegovy® raised resting heart rate by 1 to 4 beats per minute on average, and 26% of people saw an increase of 20 bpm or more.
If you notice any of these symptoms, make sure to let your healthcare provider know. They can help you adjust your treatment plan to stay safe and comfortable as your body adapts.
Other potential side effects of Wegovy®
Some side effects aren’t officially listed in the Wegovy® prescribing information, but they frequently come up in real-world experiences. Here’s what people often ask—and why these changes might occur:
Is muscle loss a side effect of Wegovy®?
Rapid weight loss can lead to some muscle mass reduction or sarcopenia, especially if you’re not eating enough protein or not strength training. This is common across most weight loss methods.
What to do: Focus on eating enough protein and adding resistance training to your routine. These help preserve lean muscle, which supports strength and metabolism during weight loss.
Is a gaunt face a side effect of Wegovy®?
Significant weight loss may lead to facial volume loss, making features appear more sunken. Since Wegovy® and Ozempic® both contain semaglutide, similar facial changes may be reported by people using either medication. This can happen with any form of weight loss, not just Wegovy®.
What to do: Stay well hydrated and talk to your provider to find a sustainable pace for weight loss.
Is feeling cold a side effect of Wegovy®?
A lower body weight and reduced calorie intake can lead to feeling chilly more often, especially if your metabolism slows slightly during weight loss.
What to do: Keep moving throughout the day. Staying active boosts circulation, which can help you feel warmer even as your weight decreases.
Is hair loss a side effect of Wegovy®?
Hair loss can happen with rapid weight loss due to the stress it places on the body, but it’s usually temporary.
What to do: Focus on a balanced diet with enough protein, iron, and key nutrients to support hair health.
Is depression a side effect of Wegovy®?
Some people report mood changes, including depression or anxiety, while taking GLP-1 medications like Wegovy®. While these are listed as possible side effects, the FDA hasn’t found a clear link between GLP-1 medications and suicidal thoughts, but they are continuing to monitor it closely.
What to do: Reach out to your healthcare provider if you notice changes in your mood or mental health. If you’re in crisis or need immediate help, contact the Suicide & Crisis Lifeline at 988.
Is increased fertility a side effect of Wegovy®?
Weight loss can improve hormone balance and ovulation, which may increase fertility, especially in people with conditions like PCOS. Wegovy® doesn’t directly cause this, but it may help your body function more regularly.
What to do: Use reliable contraception while taking Wegovy®. If you’re planning to become pregnant, talk to your healthcare provider. You should stop taking Wegovy® at least two months before trying to conceive.
If any of these symptoms are affecting your comfort or confidence, bring them up with your healthcare provider. Small adjustments in your lifestyle or routine can make a big difference.
Side effects of stopping Wegovy®
Stopping Wegovy® without a plan can lead to some unexpected changes. Here’s what can happen if Wegovy® is paused or stopped, and a couple of ways to deal with the side effects:
- Hunger can return: Since Wegovy® helps with appetite control, stopping it may make you feel hungrier or think about food more often.
- Some weight regain is common: Without the medication’s support, it’s possible to regain weight, especially if healthy habits aren’t fully in place yet.
- Easing off slowly might help: Instead of stopping abruptly, gradually reducing your dose or tapering off (with your provider’s help) may make the transition smoother.
- Habits still matter most: Daily choices like staying active, eating balanced meals, and having support make a big difference. Tools like Noom can help keep you on track, even after stopping.
Always check in with your healthcare provider first. They can help you ease off the medication in a way that supports your progress, whether that means adjusting your eating plan, adding a different treatment, or focusing more on activity.
Do females experience different side effects?
While Wegovy® isn’t known to cause side effects that are exclusive to females, some experiences may show up more often or feel a bit different due to hormonal changes and how weight loss affects the body. Here’s what to know:
- Changes in menstrual cycles: Some females report irregular periods or spotting while on Wegovy®. Rapid weight loss can affect estrogen levels, which may temporarily throw off your cycle.
- Potential benefits for PCOS: In one study, nearly 80% of females with PCOS and a BMI over 30 who responded to semaglutide treatment saw more regular periods after six months. Weight loss and improved insulin sensitivity may play a role in these benefits.
- Stronger side effects: A study suggests that females may be more likely than males to report certain side effects when taking GLP-1 medication, especially gastrointestinal ones like nausea or vomiting.
- Fertility changes: Weight loss can lead to more regular ovulation, which may increase fertility. While GLP-1 medications like Wegovy® aren’t fertility treatments, these changes can still make pregnancy more likely.
- Oral birth control might be less reliable: We don’t know for sure if Wegovy® affects how well birth control pills work, but since GLP-1 medications can delay digestion, it might impact how oral contraceptives are absorbed. Until more research is available, talk to your provider about switching to a non-oral option or using backup protection.
If you’re noticing changes in your cycle or thinking about becoming pregnant, talk to your doctor. They’ll help you decide what’s safe and the steps to take next.
Wegovy®: Severe side effects and warnings
While Wegovy® can be an effective tool for weight management, you need to be aware of potential serious side effects.
Wegovy® carries a black box warning—the FDA’s strongest safety alert—due to a possible risk of thyroid C-cell tumors observed in animal studies. It’s unknown whether this applies to humans, but if you or a family member has a history of medullary thyroid carcinoma (MTC) or Multiple Endocrine Neoplasia syndrome type 2 (MEN 2), you shouldn’t take Wegovy®.
Here are other serious side effects to watch for. If you experience these symptoms, seek medical help immediately.
- Pancreatitis: Wegovy® may trigger inflammation of the pancreas. This can cause severe, persistent abdominal pain—often radiating to the back—with or without nausea and vomiting. Seek medical attention immediately.
- Gallbladder problems: Weight loss and GLP-1 medications like Wegovy® can sometimes lead to gallstones or gallbladder inflammation (cholecystitis). Symptoms include upper right abdominal pain, nausea, fever, or yellowing of the skin or eyes.
- Kidney injury: Ongoing vomiting or diarrhea can cause dehydration, which may lead to acute kidney failure. Watch for decreased urination, swelling in your legs or feet, or unusual tiredness.
- Severe allergic reactions: Although rare, some people may experience swelling of the face, lips, tongue, or throat, trouble breathing, hives, or a severe rash. These allergic reactions can be life-threatening; seek emergency care immediately.
- Low blood sugar (hypoglycemia): Wegovy® can cause shakiness, sweating, confusion, dizziness, blurred vision, or fainting, especially in people also taking insulin or sulfonylureas.
- Increased heart rate: In clinical trials, Wegovy® was linked to a rise in resting heart rate for some users. If you notice a persistent racing heartbeat or feel like your pulse is unusually fast while at rest, notify your provider.
- Suicidal thoughts or behavior: Some people have reported experiencing new or worsening depression, anxiety, or suicidal thoughts while taking Wegovy®. The FDA hasn’t found a direct link between GLP-1 medications like Wegovy® and suicidal thoughts, but it’s still something to watch for. If you or someone you know is struggling, don’t wait—talk to your healthcare provider or reach out to the Suicide & Crisis Lifeline by calling or texting 988.
Remember, while serious side effects can happen, they’re not common. Knowing what to look out for helps you stay ahead. If you ever think you’re experiencing a medical emergency, don’t wait—call 911 or seek immediate care.
Who shouldn’t take Wegovy®
Wegovy® isn’t right for everyone, and there are specific situations where it could pose risks. According to FDA guidelines and prescribing information, you should avoid Wegovy® if any of the following apply to you:
- You or a family member has a history of medullary thyroid cancer (MTC) or MEN 2: Wegovy® carries a boxed warning due to the risk of thyroid tumors observed in animal studies.
- You’ve had allergic reactions to semaglutide or other GLP-1 medications: Symptoms may include rash, swelling, or trouble breathing.
- You’re pregnant or planning to become pregnant: Wegovy® may harm a developing fetus and should not be used during pregnancy. If you’re planning to conceive, stop using Wegovy® at least two months beforehand to allow the medication to clear your system. If you become pregnant while taking Wegovy®, discontinue use immediately and contact your healthcare provider for further guidance.
- You’re breastfeeding: It’s unknown if semaglutide passes into breast milk, so Wegovy® isn’t recommended while nursing.
Talk to your doctor before starting Wegovy® if you have a history of:
- Pancreatitis: GLP-1 medications may increase this risk, so be sure to discuss any history of pancreatitis with your provider.
- Severe gastrointestinal issues: Conditions like gastroparesis may be worsened by Wegovy®, which slows digestion.
For more detailed safety information, visit the Wegovy® safety page.
Comparing Wegovy® to other GLP-1 drugs
If you’re exploring GLP-1 medications, it helps to understand how Wegovy® compares to other popular options like Ozempic®, Zepbound®, Mounjaro®, and Saxenda®. While all of these medications can play a role in weight management or blood sugar control, they differ in how they work and what kind of side effects you might experience compared to Wegovy®.
Wegovy® vs. Ozempic® (semaglutide)
Wegovy® and Ozempic® contain the same active ingredient: semaglutide. Wegovy® is approved for weight loss of up to 2.4 mg per week, while Ozempic®, approved for diabetes and used off-label for weight loss, maxes out at 2.0 mg.
Any differences in side effects:
Wegovy® and Ozempic® are made from the same active ingredient—semaglutide—so their side effects are the same at comparable doses. Wegovy® can be prescribed at a higher maximum dose (2.4 mg vs. Ozempic®’s 2 mg), which means side effects like nausea or vomiting may be more noticeable if you reach that higher level. Your doctor will increase your dose only as needed—and only if your body tolerates it—to support steady, sustainable weight loss.
Wegovy® vs. Zepbound®/Mounjaro® (tirzepatide)
Zepbound® and Mounjaro® both contain tirzepatide, a medication that targets two hormones—GLP-1 and GIP—to help regulate appetite and blood sugar. This dual action may lead to greater weight loss compared to medications that only target GLP-1, like Wegovy®. Both Zepbound® and Mounjaro® are once-weekly injections and come in the same doses. The difference is that Zepbound® is FDA-approved for weight loss, while Mounjaro® is approved for type 2 diabetes but is often prescribed off-label to support weight loss.
Any differences in side effects:
Based on clinical trial data for Wegovy® (2.4 mg weekly) and Zepbound® or Mounjaro® (15 mg weekly), here’s how the side effects compare:
- Nausea, vomiting, constipation, and diarrhea are reported for both medications, but might be more common with Wegovy®.
Wegovy® vs. Saxenda®
Wegovy® and Saxenda® are both GLP-1 medications approved for weight management. Saxenda® contains liraglutide and is injected once daily.
Any differences in side effects:
Based on clinical trial data for Wegovy® (2.4 mg weekly) and Saxenda® (3 mg daily), here’s how the side effects compare:
- Nausea, diarrhea, and constipation are reported with both but are more common with Wegovy®.
Wegovy vs. other GLP-1s: Side-effect frequency table
Here’s a quick side-by-side comparison of how many people have reported experiencing common side effects with the highest doses of GLP-1 medications Wegovy®, Ozempic®, Zepbound®/Mounjaro®, and Saxenda®. This can help you get a clearer picture of what to expect and how the experiences might differ between treatments:
| Medication | Nausea | Vomiting | Diarrhea | Constipation | Abdominal pain |
|---|---|---|---|---|---|
| Wegovy® (2.4 mg) | 44% | 24% | 30% | 24% | 20% |
| Ozempic® (2 mg/semaglutide) | 14% | 8% | 9% | ≥5% | ≥5% |
| Zepbound®/Mounjaro® (15 mg/tirzepatide) | 28% | 13% | 23% | 11% | 10% |
| Saxenda® (3 mg mg/liraglutide) | 39% | 15% | 21% | 19% | 5% |
No single option is best for everyone. Your choice will depend on your health history, weight goals, and how comfortable you are with the side effects. A healthcare provider can help you compare your options and choose a path that works best for you.
Your next steps with Wegovy®
Wegovy® can support steady, long-term weight loss by regulating hunger and slowing digestion, but it’s important to know what comes with it. Side effects like nausea, constipation, or fatigue are common early on and tend to fade as your body adjusts. If something feels off, your provider can help you adjust your plan.
Serious side effects are rare, but knowing the warning signs helps you stay ahead of potential risks. Wegovy® isn’t right for everyone, especially if you’re pregnant or have certain medical conditions, so starting with the right support matters.
If you qualify for Noom Med, you’ll be matched with a clinician who can walk you through medication choices and prescribe them, if needed. Then, they’ll help you work through symptom management and more. With the right plan in place, you’ll be more prepared to get the results you’re looking for—safely and confidently.
Note: Ozempic® and Mounjaro® are not FDA-approved to treat obesity or for weight loss.
