Wegovy: How It’s Used for Weight Loss
Wegovy (semaglutide) is a prescription drug that’s used for weight loss in certain adults and children. Wegovy is only available as a brand-name drug. It doesn’t come in a generic version.
Wegovy comes as a liquid solution inside a single-use injection pen. It’s given as an injection under your skin.
The active ingredient in Wegovy is semaglutide. (An active ingredient is what makes a drug work.) Wegovy belongs to a group of drugs called glucagon-like peptide-1 (GLP-1) receptor agonists.
To learn more about Wegovy, see this in-depth article.
Using Wegovy for weight loss (its only approved use) may cause side effects in some people. These side effects can be mild or serious.
The lists below include some of the main side effects that have been reported in people using Wegovy. For information about other possible side effects of the drug, talk with your doctor or pharmacist.
You can also learn more from this article about Wegovy side effects or from the drug’s prescribing information.
Note: After the Food and Drug Administration (FDA) approves a medication, it tracks and reviews side effects of the drug. If you develop a side effect while taking Wegovy and would like to inform the FDA, visit MedWatch.
What are Wegovy’s mild side effects?
Mild side effects that have been reported with Wegovy include:
- nausea and vomiting
- belly pain
- upset stomach or heartburn
- burping or flatulence (gas)
- bloating
- diarrhea
- constipation
- stomach flu
- fatigue (low energy)
- headache
- dizziness
In many cases, mild side effects from the drug can be temporary. Some side effects may be easy to manage, too. But if side effects last for a longer time, or if they bother you or become severe, talk with your doctor or pharmacist.
What are Wegovy’s serious side effects?
Some serious side effects have been reported with Wegovy, but they’re not common. Serious side effects that have been reported include:
- low blood sugar
- fast heart rate
- kidney problems, such as kidney failure
- gallbladder problems, such as gallstones
- pancreatitis (swelling of your pancreas)
- risk of thyroid cancer*
- allergic reaction†
Call your doctor right away if you have any serious side effects while using Wegovy. If the side effects seem life threatening or if you think you’re having a medical emergency, call 911 or your local emergency number immediately.
* Wegovy has a boxed warning for this side effect. To learn more, see the “What should I know before using Wegovy?” section below.
† An allergic reaction is possible after using Wegovy. But this side effect wasn’t reported in studies of Wegovy.
Here are the answers to some frequently asked questions about Wegovy.
Is Wegovy the strongest weight loss drug? How does it compare with other drugs used for weight loss?
Wegovy is used for long-term weight management. Other drugs prescribed for this use include liraglutide (Saxenda), phentermine/topiramate (Qsymia), and naltrexone/bupropion (Contrave).
Saxenda belongs to the same group of drugs as Wegovy: glucagon-like peptide-1 (GLP-1) receptor agonists. These drugs reduce appetite and make you feel fuller after eating. They’re both given by injection. Saxenda is injected once daily, while Wegovy is injected once weekly.
Qsymia comes as a capsule and Contrave comes as a tablet. Each is swallowed once per day. These drugs work differently than Wegovy and Saxenda. They reduce appetite and food cravings by affecting various message pathways in your brain.
Wegovy isn’t “stronger” than other weight loss drugs, but it may help you lose more weight. Recent guidelines from the American Gastroenterological Association note that for most people, Wegovy will likely be more effective for weight loss than Saxenda, Qsymia, or Contrave.
But this might not be the case if you have type 2 diabetes. In studies, Wegovy was less effective than Ozempic for weight loss in people with type 2 diabetes.
Wegovy may not be right for everyone. Your doctor can tell you more about how Wegovy compares with other treatment options. And they can help you find the best option for you.
How fast do you lose weight on Wegovy?
Wegovy helps you lose weight gradually over time. You may start losing weight in the first few weeks of treatment. You’ll likely continue to lose weight over the following months.
To learn more about what to expect from your Wegovy treatment, talk with your doctor.
Do I have to take Wegovy long term?
Yes, Wegovy is meant to be taken long term to help manage your weight. You’ll take it as part of a long-term weight management plan, which will also include a reduced-calorie diet and regular exercise.
If you have questions about taking Wegovy long term, talk with your doctor.