Wegovy (semaglutide) and Mounjaro (tirzepatide) are prescription drugs that may be used for weight loss and management. But only Wegovy has been FDA-approved for this use. Mounjaro is approved to help treat type 2 diabetes.

Both Wegovy and Mounjaro come as a liquid solution given as an injection under the skin.

This article explains the main ways that Wegovy and Mounjaro are alike and different. For more information about these drugs, including details about their uses, see these in-depth articles on Wegovy and Mounjaro.

Both Wegovy and Mounjaro are prescribed along with diet and exercise to help with weight loss.

Wegovy is FDA-approved for chronic (long-term) weight management in certain situations. Specifically, the drug can be used in people with obesity or those who are overweight and have certain weight-related conditions, including high blood pressure.

Mounjaro isn’t approved for these uses, but it can be prescribed off-label for them. (With off-label use, a drug is prescribed for a condition it isn’t approved to treat.) Mounjaro is FDA-approved to help manage blood sugar levels in adults with type 2 diabetes. To learn more about using Mounjaro for weight loss and weight management, see this article.

To learn more about Wegovy or Mounjaro for treating your condition, talk with your doctor.

A generic drug contains an exact copy of the active ingredient in a brand-name medication. (An active ingredient is what makes a drug work.) To find out whether Wegovy or Mounjaro is available as a generic, see below.

  • Wegovy:
    • Available as a generic: no
    • Active ingredient: semaglutide
  • Mounjaro:
    • Available as a generic: no
    • Active ingredient: tirzepatide

Wegovy or Mounjaro and children

Wegovy is approved for weight loss and weight management in certain children ages 12 years and older. Mounjaro is not approved for any use in children.

For more information about the use of Wegovy in children, see this article. You can also talk with your child’s doctor.

Wegovy and Mounjaro are approved to treat different conditions. Wegovy is used for weight loss and weight management in certain people who are overweight. Mounjaro is sometimes used off-label* for this condition, but it’s only approved to help treat type 2 diabetes.

Both medications are given as an injection under the skin of your abdomen or upper thigh. Or a caregiver may inject either drug under the skin of your upper arm. Your doctor will show you or a caregiver how to inject Wegovy or Mounjaro. They’ll also tell you how often to use it.

To learn more about the dosages for all conditions these drugs treat, see the dosage articles for Wegovy and Mounjaro. To learn more about Mounjaro’s dosage for weight loss and management, see the “How to use Mounjaro” section of this article.

* With off-label use, a drug is prescribed for a condition it isn’t approved to treat.

If you use Wegovy or Mounjaro, you may experience mild to serious side effects.

For more information about possible side effects, see the side effect articles on Wegovy and Mounjaro.

Mild side effects

Wegovy and Mounjaro may cause mild side effects. The table below lists examples of mild side effects that have been reported with these drugs.

WegovyMounjaro
digestive side effects, such as diarrhea, nausea, constipation, and indigestion (upset stomach)✓✓
dizziness✓
fatigue (low energy)✓
hair loss✓
headache✓
stomach flu✓
the common cold✓
injection site reactions, such as swelling and itching around the injection area✓✓
mild increases in heart rate✓✓

This table may not include all mild side effects of these medications. For more information on mild side effects of the two drugs, see the Wegovy prescribing information and Mounjaro prescribing information.

Serious side effects

In addition to the mild side effects described above, serious side effects may occur in people using Wegovy or Mounjaro. See the table below for a list of serious side effects that have been reported with these drugs.

WegovyMounjaro
hypoglycemia (low blood sugar)✓✓
pancreatitis (swelling of the pancreas)✓✓
cholecystitis (swelling of the gallbladder) and gallstones✓✓
severe digestive problems, such as severe diarrhea, which may lead to dehydration or kidney problems✓
risk of thyroid cancer*✓✓
allergic reaction✓✓

For more information about possible side effects, see these side effect articles on Wegovy and Mounjaro.

To learn about your specific risk for serious side effects from Wegovy or Mounjaro, talk with your doctor or pharmacist.

* Wegovy and Mounjaro have a boxed warning for this side effect. A boxed warning is the most serious warning from the Food and Drug Administration (FDA). To learn more, see the “What are the warnings of Wegovy and Mounjaro?” section below.

You may wonder whether Wegovy or Mounjaro are effective for your condition.

Wegovy is used for weight loss and weight management in certain people with obesity or overweight. Mounjaro is sometimes used off-label for these conditions. (With off-label use, a drug is prescribed for a condition it isn’t approved to treat.) But Mounjaro is only FDA-approved to help manage blood sugar levels in adults with type 2 diabetes.

Studies of Wegovy and Mounjaro have shown that both drugs are effective for their approved uses. Also, studies looking at Mounjaro for managing type 2 diabetes have shown that the drug leads to weight loss. But it’s important to note that your results from Wegovy or Mounjaro may differ from those seen in studies. Talk with your doctor about whether one of these drugs is right for you.

If you’d like to read more about how each drug performed in studies, see the prescribing information for Wegovy and Mounjaro. And to learn more about using Mounjaro for weight loss and weight management, see this article.

Whether you have health insurance or not, cost may be a factor when you’re considering these drugs. Visit Optum Perks* to get price estimates for Wegovy and Mounjaro when you use coupons from the site. It’s important to note that Optum Perks coupons cannot be used with any insurance copays or benefits.

Keep in mind that what you’ll pay for either drug will depend on your treatment plan, health insurance coverage, and the pharmacy you use.

Wegovy and Mounjaro are both brand-name drugs. These drugs do not have generic forms. You’ll usually pay more for brand-name drugs than for generics.

For other resources that might help you save on the price of these drugs, see the cost articles for Wegovy and Mounjaro.

* Optum Perks is a sister site of Healthline.

Wegovy and Mounjaro may not be right for you if you have certain medical conditions or other factors that affect your health. These may be referred to as warnings.

The two drugs share some of the same warnings, but they also have different ones. Some of these warnings are mentioned below. Before you start using Wegovy or Mounjaro, be sure to talk with your doctor to see if these warnings apply to you.

Boxed warning: Risk of thyroid cancer

Wegovy and Mounjaro both have a boxed warning. A boxed warning is the most serious warning from the Food and Drug Administration (FDA). It alerts doctors and patients about drug effects that may be dangerous.

Risk of thyroid cancer. Animal studies have shown that using semaglutide (the active ingredient in Wegovy) or tirzepatide (the active ingredient in Mounjaro) caused thyroid cancer in mice and rats. (An active ingredient is what makes the drug work.)

Keep in mind that animal studies don’t always predict what happens with humans. It isn’t known for certain whether Wegovy or Mounjaro increases the risk of thyroid cancer in humans. But due to the risk, doctors usually won’t prescribe Wegovy or Mounjaro for certain people, including those with either:

Symptoms of thyroid cancer include:

If you have symptoms of thyroid cancer during treatment with Wegovy or Mounjaro, tell your doctor right away. They may order tests to check for thyroid cancer.

For more information about this warning, talk with your doctor.

Other warnings

In addition to boxed warnings, Wegovy and Mounjaro have other warnings.

Before using Wegovy or Mounjaro, talk with your doctor if any of the following conditions or health factors apply to you.

To learn more about these drugs, see these in-depth articles on Wegovy and Mounjaro.

Help is out there

If you or someone you know is in crisis and considering suicide or self-harm, please seek support:

If you’re calling on behalf of someone else, stay with them until help arrives. You may remove weapons or substances that can cause harm if you can do so safely.

If you are not in the same household, stay on the phone with them until help arrives.

The short answer: It’s possible, if your doctor recommends it.

Details: Both Wegovy and Mounjaro are prescribed along with diet and exercise to help with weight loss and weight management. It may be possible to switch between the two drugs for these purposes. Your doctor can tell you more.

Reminder: You shouldn’t switch drugs or stop your current treatment unless your doctor recommends it.

Wegovy and Mounjaro have different approved uses. Wegovy is used for weight loss and management, while Mounjaro can be used off-label for this purpose.

If you have questions about these drugs, talk with your doctor or pharmacist. They can tell you whether Wegovy or Mounjaro is right for you. Examples of questions you may want to ask include:

  • Do I have a higher risk of hypoglycemia (low blood sugar) with either Wegovy or Mounjaro?
  • How do Wegovy and Mounjaro compare with other treatments for weight loss and weight management?
  • Do any of my health conditions make Wegovy or Mounjaro less safe for me?
  • What diet changes and exercise goals do you recommend for me while using Wegovy or Mounjaro?

To learn more about Wegovy, see these articles:

To learn more about Mounjaro, see these articles:

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Disclaimer: Healthline has made every effort to make certain that all information is factually correct, comprehensive, and up to date. However, this article should not be used as a substitute for the knowledge and expertise of a licensed healthcare professional. You should always consult your doctor or another healthcare professional before taking any medication. The drug information contained herein is subject to change and is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. The absence of warnings or other information for a given drug does not indicate that the drug or drug combination is safe, effective, or appropriate for all patients or all specific uses.