Semaglutide Side Effects: What to Expect & How Long They Last

Semaglutide is the active ingredient in medications like Ozempic^® and Wegovy^®. Ozempic is approved by the FDA (U.S. Food and Drug Administration) to treat type 2 diabetes, and Wegovy^® is FDA-approved for weight loss.

Semaglutide side effects are common when starting treatment, but the long-term health benefits of weight loss are significant for people with a high BMI (body mass index).

Research shows that losing just 5 percent of body weight can help prevent or manage serious weight-related health conditions, like heart disease, cardiovascular disease, high blood pressure (hypertension), type 2 diabetes, and breathing issues.

In this guide, we’ll cover everything you need to know about semaglutide side effects, including what to expect, how long they last, and long-term considerations.

Semaglutide side effects are common, but most are mild to moderate in nature. Frequently reported side effects include:

• Nausea

• Diarrhea

• Constipation

Keep scrolling for details.

Semaglutide Nausea

Nausea is the most common of all the semaglutide side effects. 

In clinical trials on Ozempic^® and Wegovy^® (which contain semaglutide), nausea was reported in:

• 15.8 percent of people taking a 0.5-milligram (mg) dose of Ozempic 

• 20.3 percent of those taking 1 mg of Ozempic

• 44 percent of participants taking 2.4 mg of Wegovy^®

Why Does Semaglutide Make You Nauseous?

It’s unclear what causes semaglutide nausea, but it might be due to the drug’s ability to slow gastric emptying (how quickly food moves through your system). Though this can help you feel full faster and reduce the urge to overeat, it could also contribute to nausea.

Minimizing Semaglutide Nausea

Luckily, there are treatments to help. Here are some options:

• Prescription anti-nausea medication (if eligible, included with your Hers treatment plan at no extra cost)

• Over-the-counter (OTC) anti-nausea meds like Pepto Bismol^® (bismuth subsalicylate)

• Eating smaller, more frequent meals and stopping when you feel full

• Drinking plenty of water (but avoiding drinking during meals and 30 to 60 minutes before and after eating)

• Avoiding high-fat foods that can trigger nausea, like fatty meats and fried foods

Check out our guide to semaglutide nausea to learn more about this side effect.

Semaglutide Diarrhea 

Diarrhea is another common semaglutide side effect.

In trials, it was reported in:

• 8.5 percent of people taking 0.5 mg of Ozempic

• 8.8 percent of those taking 1 mg of Ozempic

• 30 percent of participants taking 2.4 mg of Wegovy^®

Again, it’s not entirely clear what’s behind this. But semaglutide might change how quickly food moves through your intestines and the absorption of glucose (blood sugar) and lipids (fatty compounds), which may cause diarrhea.

Here’s what you can try to treat semaglutide diarrhea:

• Talk to your healthcare provider about OTC meds like loperamide (Imodium^®).

• Make sure you’re drinking enough water.

• Aim to eat more high-fiber foods or try a prebiotic fiber supplement like Benefiber^®.

• Avoid foods like dairy products, coffee, and alcohol while experiencing diarrhea.

• Eat foods easy on the gut, like chicken, broth, rice, carrots, and peeled fruit.

Semaglutide Constipation

Constipation is another common side effect of semaglutide. It’s reported in:

• 5 percent of people taking a 0.5-mg dose of Ozempic

• 3.1 percent of those taking 1 mg of Ozempic

• 24 percent of participants taking 2.4 mg of Wegovy^® 

Once more, though, this side effect tends to decrease over time.

What’s causing this one? GLP-1 drugs (glucagon-like peptide-1 receptor agonists) like semaglutide can delay the movement of food through the intestines and increase water absorption, which might cause constipation and related stomach pain or discomfort.

You might also change your eating habits when you feel fuller, like drinking less water and eating less fiber, which could contribute to constipation.

To treat semaglutide constipation:

• Eat more fiber (from foods like fruit, veggies, brown rice, beans, and lentils)

• Drink more water

• Get more physical activity

• Consider OTC stool softeners

Everyone reacts differently to medication, so there’s no set time frame for how long semaglutide side effects will last. But in general, they tend to pop up when starting treatment, especially at high dosages.

A review of studies conducted by Novo Nordisk (the manufacturer of Ozempic, Wegovy^®, and oral semaglutide Rybelsus^®) found that gastrointestinal side effects can happen in the first eight to 12 weeks of treatment with Ozempic and Rybelsus.

Another review of studies by Novo Nordisk found that:

• Nausea might last eight days or less for Ozempic and Wegovy^®

• Diarrhea may last about three days on Wegovy^®

• Constipation might last roughly 47 days on Wegovy^®

You’ll most likely lose weight on semaglutide (you’re probably hoping for that particular side effect!). But this could lead to a few weight-loss-related side effects, such as:

Fatigue 

Does semaglutide make you tired? Fatigue is reported in less than 0.4 percent of people in Ozempic clinical trials and 11 percent of participants in Wegovy^® trials. But people are reporting this side effect on social media.

If you find yourself feeling tired on semaglutide, it might be down to eating fewer calories, low blood sugar, or side effects like vomiting and diarrhea causing dehydration.

To help, make sure you’re:

• Getting enough sleep — aim for seven to nine hours of quality shut-eye each night

• Moving daily (counterintuitively, exercise can improve fatigue)

• Eating a range of nutritious foods

• Drinking enough water

Learn more about semaglutide and fatigue.

“Semaglutide Face“ 

When you lose a significant amount of weight, your body composition changes. Some of these changes, like losing facial fat and lean muscle, might be less desirable than others.

If you’ve heard the term “Ozempic face“ or “semaglutide face,“ you might be a little worried about how weight loss medications will affect your appearance. But there’s no need to panic — “Ozempic face” isn’t a real side effect of the medication. It’s just something that could happen with any form of weight loss (with medication or otherwise).

As you lose facial fat, you may notice slight sagging or the appearance of fine lines. This may be more apparent in people with mature skin that’s lost some of its elasticity. Your skin might naturally retract back after you’ve lost weight and kept it off for a while. If not, certain cosmetic treatments can help.

Muscle Loss

Whenever someone loses a significant amount of weight, they’re also at risk of muscle loss. When you maintain a calorie deficit (eating fewer calories than you burn), your body starts breaking down fat for fuel. And it can break down lean muscle, too, if you’re not careful.

That’s why Weight Loss by Hers is designed to help you lose fat and maintain muscle. How? The trick is to prioritize protein.

When you sign up with Weight Loss by Hers, you get access to easy, high-protein recipes designed for people taking GLP-1s. We’ll start you off with a seven-day meal plan and plenty of tips and tricks for fitting more protein into your diet.

You can also use our protein calculator to get personalized recommendations for how much protein to eat based on factors like your weight, goals, and activity levels.

Hers also offers doctor-recommended meal replacement kits that make it quick and easy to fit more protein into your day. These nutrition bars can be used as meal replacements or snacks when you’re on the go.

Other protein sources include:

• Chicken

• Turkey

• Fish

• Eggs

• Nuts and seeds

• Soy products like tofu and tempeh

• Nutritious protein bars and shakes

In addition to eating more protein, strength training can help you build and maintain the muscle you have. That could include:

• Doing bodyweight exercises

• Using dumbbells and resistance bands

• Using resistance machines in the gym

• Weight lifting

Aim for at least two sessions a week.

Trying to fit more protein into your diet? Check out our Guide to Meal Prep.

Does Semaglutide Cause Hair Loss?  

Hair loss is a rare side effect of semaglutide, though there are anecdotal reports and some Reddit chit-chat about it. In Wegovy^® trials, it was reported in 3 percent of people — it wasn’t reported in Ozempic trials at all.

There’s not much research into what could cause potential hair loss, but it’s thought it might be due to a disrupted hair growth cycle. There’s even speculation that GLP-1 receptor agonists like semaglutide could treat hair loss — just to make matters more confusing.

If you notice hair loss, it could actually be caused by something else entirely, like stress, age, or rapid weight loss. If you’re concerned about excessive shedding, message your care team in the app, as a range of treatment options from Hers can help.

To help with hair loss, consider:

• Hair loss medications like minoxidil or finasteride  

• Supplements like biotin 

• Microneedling or laser therapy 

• Reducing stress (easier said than done, of course)

• Eating more protein

Heard semaglutide side effects are worse in women? Some studies show women report side effects from diabetes medications more often than men. But this is reported side effects (men may report them less than women) and diabetes drugs as a whole (not just semaglutide).

Other research states that side effects are more frequent in women on GLP-1s. But this also includes drugs beyond semaglutide injections, so much more research is needed on this front.

Here’s what else we know about semaglutide side effects in women.

Semaglutide and Fertility 

More research is needed, but right now, there’s no evidence that semaglutide negatively affects fertility. Infertility hasn’t been reported as one of the side effects of Semaglutide.

In fact, it could even improve fertility (hence the TikTok buzz around “Ozempic babies“). How so? Semaglutide can treat obesity and type 2 diabetes, which are linked to fertility problems. And it may normalize the length of your menstrual cycle if you have PCOS (polycystic ovary syndrome).

Learn more in our guide to Ozempic and Fertility.

Semaglutide and Birth Control 

More research is needed to know if semaglutide impacts hormonal birth control.

Theoretically, it could. Semaglutide slows gastric emptying, which can impact how the body absorbs medications like the Pill and emergency contraceptives like Plan B^®.

Vomiting and diarrhea can also mess with the effectiveness of oral contraceptives.

Tell your prescribing healthcare provider if you take oral contraceptives. They can let you know if you need to use a different method to prevent pregnancy.

Semaglutide and Periods 

Semaglutide itself probably won’t impact your periods, but the weight loss you experience on the drug might. (It’s also worth noting that weight loss might improve your menstrual cycle.)

Substantial weight loss may cause irregular periods or make your periods stop altogether (known as amenorrhea).

On the other hand, obesity is linked to:

• Irregular periods

• Heavy periods 

• Premenstrual syndrome (PMS) 

So treating obesity might help regularize your menstrual cycle and make your periods more manageable. More research is needed to confirm this, though.

Learn more: How Ozempic Affects Your Period.

Semaglutide was originally formulated as a treatment for type 2 diabetes, intended for long-term use. But there are a few potential long-term side effects to be aware of. Rest assured, these are rare.

In Ozempic trials and Wegovy^® trials, potential side effects include:

• Pancreatitis (inflammation of the pancreas)

• Kidney problems like acute kidney injury, especially associated with nausea and vomiting 

• Gallbladder problems like gallstones and gallbladder disease

• Increased heart rate

• Mental health issues

• Diabetic retinopathy (an eye condition that can happen to people with diabetes)

• Thyroid cancer or thyroid tumors (based on research in rodents)

For folks with a high BMI, the long-term health benefits of lasting weight loss may outweigh the risks.

Message your care team in the app if you’re concerned about long-term side effects. They help you weigh the risks and benefits. 

Semaglutide was originally developed to help people with type 2 diabetes manage their blood sugar levels. That means it’s intended for long-term, even life-long, use.

You don’t need to take semaglutide forever if you don’t want to. But it can help you manage your weight long-term, as some people regain some of the weight they’ve lost when they stop taking weight loss medication.

Learn more: How long can you take semaglutide for weight loss?

Brand-name Ozempic and other semaglutide drugs are usually prescribed alongside lifestyle changes like eating more healthfully. But what exactly should you be eating and avoiding?

As for what to avoid, there isn’t an official no-go list, but you’ll want to steer clear of foods that may trigger increased gastrointestinal side effects.

That might include:

• Fatty meats

• Fried foods

• Sugary foods and drinks

• Acidic foods like tomatoes and citrus fruits

• Spicy foods

• Garlic and onions

Consider keeping a food diary to figure out your triggers, if you have any.

And now for what to add to your grocery list. In general, you’ll want to eat nutritious, whole foods like:

• Lean protein

• Low-fat dairy products

• Fruits and veggies

• Nuts and seeds

• Legumes like lentils and beans

• Whole grains like brown rice and oatmeal

Remember to prioritize protein to help with muscle growth and maintenance. Protein can also help reduce appetite and curb food cravings. Win-win.

Learn more about what to eat on Ozempic (and what to avoid).

Semaglutide and Alcohol

We have to do a special shout-out to alcohol.

While you can technically drink alcohol on semaglutide, it may make the drug less effective and make side effects worse. Consider enjoying alcohol in moderation every now and again or avoiding it altogether.

Learn more in our guide to Ozempic and alcohol.

All these semaglutide side effects can sound overwhelming. But remember, the common ones are usually mild and temporary, and the serious side effects are rare. 

Here’s what to keep in mind:

• The most common side effects of semaglutide are gastrointestinal. They’re often mild and subside over time as your body gets used to the medication. There’s also plenty you can do to make them more manageable, if needed.

• Semaglutide is considered safe and effective. It’s recommended as a treatment for weight loss and long-term weight management.

• The benefits of semaglutide often outweigh its risks. Semaglutide can help you lose weight, improving your quality of life and health in the short and long term. So you might find the side effects are worth it for the benefits.

Finally, don’t be afraid to discuss any concerns with a medical provider. They’re there to help.

If you get weight loss treatment through Hers, you’ll have ongoing, unlimited access to healthcare providers to get advice about any side effects that crop up. You can also get prescription tweaks, if needed, and anti-nausea medication included with your plan.

Ready to kickstart your weight loss journey? Take our free online weight loss assessment to find out which weight loss medications could work best for you.