Ozempic vs. Wegovy vs. Zepbound vs. Mounjaro: what’s the difference?

 Ozempic, Wegovy, Zepbound, and Mounjaro are all GLP-1 prescription medications that have become popular for weight loss in addition to their effectiveness in treating type 2 diabetes.

Each pair of medications shares the same active ingredient but has different brand names, indicating the conditions they are intended to treat. Mounjaro and Zepbound are two brand-name versions of tirzepatide. Similarly, Ozempic and Wegovy are two brand-name medications that contain semaglutide.

Here is a quick look at the main differences between Ozempic (semaglutide), Wegovy (semaglutide), Zepbound (tirzepatide), and Mounjaro (tirzepatide).

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Ozempic and Wegovy contain the same active ingredient: semaglutide. Semaglutide belongs to a medication class called glucagon-like peptide-1 receptor agonists (or "GLP-1s" for short). This class was originally developed for treating diabetes, but weight loss was quickly noticed as an added benefit.

Overall, Ozempic and Wegovy are similar in more ways than they are different. Similarities include:

• Route of administration: Both medications are available as a daily pill or subcutaneous (under-the-skin) injection.

• Dosing schedule: Injectable Ozempic and Wegovy are administered once weekly. The Ozempic and Wegovy pills are taken once daily.

• Manufacturer: Both medications are made by Novo Nordisk.

• Safety profile: Both medications carry similar warnings and precautions.

• High cost: Both medications are expensive, with no generic alternatives available.

The main difference between Ozempic and Wegovy is the specific indication for which the Food and Drug Administration (FDA) has approved them. Ozempic was first approved in 2017 to treat type 2 diabetes, with Wegovy following in 2021 for weight management. There are also some differences in the available dosage strengths of each medication; specifically, Wegovy dosages are higher than Ozempic dosages.

Another key difference is the dosage form. Both Ozempic and Wegovy come as prefilled injector pens. Ozempic pens contain multiple doses and require a new pen needle for each injection. In contrast, Wegovy is a single-use injection pen with a built-in needle. Both Ozempic and Wegovy are also available as oral medications.

What are Ozempic and Wegovy used for?

Ozempic injection and pill are approved for the following uses, according to the FDA labeling:

• Controlling blood sugar levels in adults with type 2 diabetes mellitus, along with a healthy diet and increased exercise

• Reducing the risk of major heart-related complications in adults with both type 2 diabetes and heart disease

• Reducing the risk of kidney decline in adults with both type 2 diabetes and chronic kidney disease (injection only)

Healthcare providers may prescribe a medication for other off-label uses if they deem it appropriate. For example, Ozempic is commonly prescribed off-label for weight loss.

While Ozempic is only officially approved for people with type 2 diabetes, Wegovy is FDA-approved for:

• Weight loss and chronic (long-term) weight management, alongside a healthy eating plan and increased exercise, in adults with obesity or with overweight and a weight-related health condition (e.g. high blood pressure, high cholesterol, type 2 diabetes mellitus)

  • Wegovy injection is approved for children ages 12 years and older with obesity

• Reducing the risk of major heart-related complications in adults with both obesity or overweight and heart disease

• Treating noncirrhotic metabolic dysfunction-associated steatohepatitis (MASH, or fatty liver disease). Note: only the Wegovy injection is approved for this condition.

How do Ozempic and Wegovy work?

Semaglutide is the active ingredient in Ozempic and Wegovy. It works by mimicking the body’s natural GLP-1 hormone. Specifically, semaglutide works by:

• Boosting insulin while reducing glucagon, which helps regulate blood sugar levels

• Slowing down the digestive system so food takes longer to leave the stomach, leading to a longer-lasting feeling of fullness

• Sending signals to the brain indicating fullness

Ozempic vs. Wegovy dosing 

Injectable Ozempic and Wegovy are both taken once a week on the same day. The Ozempic and Wegovy pills are taken once daily in the morning on an empty stomach. The dosing schedule starts at a low dose; the prescribing healthcare provider will gradually increase the dose based on tolerability until the target maintenance dosage is reached.

The injection sites for Ozempic and Wegovy are the abdomen, outer thigh, or back of the upper arm. These medications are given via subcutaneous injection, meaning they are injected just under the skin.

Wegovy pens come with a needle already attached and are meant for single use, disposed of after each injection. Ozempic pens, on the other hand, contain multiple doses — a new needle is attached to the pen for each injection and then discarded. The exact number of doses per Ozempic pen varies depending on the prescribed dosage.

The table below compares the typical dosing schedule for Ozempic vs. Wegovy:

Ozempic vs. Wegovy side effects

Ozempic and Wegovy share similar side effects, which are mostly gastrointestinal in nature. However, Wegovy has a longer list of side effects. The following are the most common side effects of Ozempic and Wegovy in clinical trials:

Keep in mind that these side effects are typically dose-dependent, meaning they are more likely at higher doses. And because Wegovy contains a higher dose of semaglutide than Ozempic, it may be more likely to cause side effects.

Ozempic vs. Wegovy cost 

Without insurance, Ozempic costs more than Wegovy. Here is a look at the typical prices for Wegovy vs. Ozempic:

• Ozempic costs $1,027.51 per month (list price). Without insurance, Ozempic costs $900–$1,100 per month on Ro (see pricing details).

• Wegovy costs $1,349.02 per month (list price). On Ro, cash payers can get the Wegovy pen for $199–$349 per month or the Wegovy pill for $149–$299 per month, depending on the dosage (see pricing details).

Ozempic and Mounjaro are similar in that both treat type 2 diabetes. However, Mounjaro has a different active ingredient (tirzepatide) and mimics two hormones: GLP-1 and glucose-dependent insulinotropic polypeptide (GIP). Its dual GLP-1 and GIP mechanism may explain why Mounjaro is more effective than Ozempic at lowering blood sugar levels and body weight.

Here are some of the key differences between Ozempic and Mounjaro:

• Active ingredient: Ozempic’s is semaglutide, while Mounjaro’s is tirzepatide.

• Manufacturer: Ozempic is made by Novo Nordisk, while Mounjaro is made by Eli Lilly.

• FDA-approved indications: Both medications are approved to treat type 2 diabetes. But Mounjaro can be prescribed to adults and children ages 10 years and older. Also, only Ozempic is additionally approved to reduce cardiovascular risk or slow kidney decline in people with type 2 diabetes and heart disease or kidney disease, respectively.

Here are some of the key similarities between Ozempic and Mounjaro:

• Mechanism of action: Both medications work by improving the way your body processes sugar. They also help people feel full faster and for longer after eating.

• Route of administration: Both medications are injected under the skin (subcutaneous injection). Ozempic is also available as an oral tablet.

• Dosing schedule: Both injectable Ozempic and Mounjaro are taken once weekly. The Ozempic pill is taken once daily.

• Safety profile: Both medications carry similar warnings and precautions.

• High cost: Both medications are expensive, with no generic alternatives available.

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Ozempic vs. Mounjaro dosing 

Injectable Ozempic and Mounjaro are both taken once a week on the same day, via a subcutaneous injection into the abdomen, outer thigh, or back of the upper arm. The Ozempic pill is taken daily in the morning on an empty stomach. 

The dosing schedule for both Mounjaro and Ozempic starts with a low dose and is gradually increased until a maintenance dosage that adequately controls blood sugar levels is reached.

One thing that differs between Ozempic and Mounjaro is the pen design. Each dose of Mounjaro comes in its own single-dose pen, while Ozempic pens contain multiple doses.

Another key difference in dosing is how long it takes to reach a maintenance dosage. With Ozempic, it can take up to four months, while with Mounjaro, it can take up to five months.

The table below compares the typical dosing schedule for Mounjaro and Ozempic:

Ozempic vs. Mounjaro side effects

Ozempic and Mounjaro share similar side effects, which are mostly gastrointestinal in nature. Here’s a list of the most common side effects of Mounjaro and Ozempic that affected at least 5% of people in clinical trials:

Ozempic vs. Mounjaro cost 

Without insurance, Mounjaro costs more than Ozempic. Here is a look at the typical prices for Mounjaro vs. Ozempic:

• Ozempic has a list price of $1,027.51 per month. Without insurance, Ozempic costs $900–$1,100 per month on Ro (see pricing details).

• Mounjaro costs $1,112.16 per month (list price). Mounjaro is primarily covered through insurance; cash-pay pricing on Ro is not currently available.

Zepbound and Mounjaro contain an identical active ingredient: tirzepatide. Tirzepatide is a dual GLP-1 and GIP receptor agonist. While tirzepatide functions similarly to other GLP-1 receptor agonists, the additional GIP component may offer a unique weight loss advantage.

Mounjaro and Zepbound are similar in numerous ways, such as:

• Active ingredient: Tirzepatide

• Mechanism of action: Both medications work by improving the way the body processes sugar. They also help people feel full faster and for longer after eating.

• Route of administration: Both medications are injected under the skin (subcutaneous injection).

• Dosing schedule: Mounjaro and Zepbound are administered once weekly.

• Manufacturer: Both medications are made by Eli Lilly.

• Safety profile: Both medications carry similar warnings and precautions.

• High cost: Both medications are expensive, with no generic versions available.

The main difference between Mounjaro and Zepbound is their FDA-approved indications (official uses). The FDA approved Mounjaro for diabetes in 2022 and Zepbound for weight loss in 2023. Zepbound is additionally approved for obstructive sleep apnea in adults with obesity.

What are Zepbound and Mounjaro used for?

The FDA approved Mounjaro to help manage blood sugar levels in adults with type 2 diabetes mellitus, alongside a healthy diet and increased exercise. While Mounjaro isn’t specifically approved for weight loss, healthcare providers may prescribe it off-label for this purpose. 

In contrast, the FDA approved Zepbound for obstructive sleep apnea in adults with obesity and for chronic (long-term) weight management, alongside a healthy eating plan and increased exercise, in adults with obesity or with overweight and at least one weight-related health condition, such as:

• High blood pressure

• High cholesterol

• Obstructive sleep apnea

• Type 2 diabetes

• Cardiovascular disease (heart and/or blood vessel problems)

How do Zepbound and Mounjaro work?

Zepbound and Mounjaro contain the same active ingredient (tirzepatide), so they work the same way. Tirzepatide has a dual mechanism to help reduce blood sugar levels and promote weight loss. The first mechanism involves GLP-1 and is identical to how Ozempic and Wegovy work. The second mechanism involves a different hormone called GIP and works in a similar but not identical way to GLP-1.

Like GLP-1, GIP is a natural hormone produced by the body. When blood sugar rises, GIP signals the pancreas to release more insulin to bring it back down. Tirzepatide mimics GIP and stimulates the release of insulin.

As with GLP-1, GIP also has a slowing effect on the digestive tract. GIP keeps food in the stomach for longer, creating a faster and longer-lasting feeling of being full. This results in less food intake, which directly promotes weight loss.

Zepbound vs. Mounjaro dosing

Despite their different uses, Zepbound and Mounjaro share similar dosing schedules. 

Zepbound and Mounjaro come as pens containing a solution injected under the skin of the abdomen, outer thigh, or back of the upper arm. Similar to Wegovy, both Zepbound and Mounjaro are one-time-use pens with an attached needle. They are also available as multi-dose vials, where the dose is drawn each week using a separate needle and syringe, and as KwikPens, which contain multiple doses in a single pen.

Zepbound and Mounjaro are administered once weekly on the same day each week. The starting dose and schedule for increasing the dose are identical for both medications. However, not everyone can tolerate increasing the dose this quickly, and some people don’t reach the maximum dose of 15 mg due to side effects. Patients should follow the dosage recommended by their healthcare provider.

The table below shows the typical dosing schedule for Zepbound and Mounjaro.

Zepbound vs. Mounjaro side effects

Because they share the same active ingredient, you might think Zepbound and Mounjaro have the same side effects. While they have many side effects in common, there are some slight differences in side effects reported in clinical trials, likely because the populations studied were different. Here’s a list of the most common side effects of Zepbound and Mounjaro in clinical trials:

Zepbound vs. Mounjaro cost

Without insurance, Zepbound costs less than Mounjaro. Here is a look at the typical prices for Zepbound vs. Mounjaro:

• Zepbound costs $1,086.37 per month (list price). On Ro, cash payers can get Zepbound multi-dose vials or KwikPens for $299–$449 per month, depending on the dosage.

• Mounjaro costs $1,112.16 per month (list price).

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Here are some of the key differences between Zepbound and Wegovy:

• Active ingredient: Wegovy’s is semaglutide, while Zepbound is tirzepatide.

• Manufacturer: Wegovy is made by Novo Nordisk, while Zepbound is made by Eli Lilly.

• FDA-approved indications: Both medications are approved for weight loss. But Wegovy is also approved for treating fatty liver disease and for reducing cardiovascular risk in people with heart disease and obesity or overweight. And Zepbound is additionally approved for obstructive sleep apnea in people with obesity. 

• Route of administration: Both medications are injected under the skin (subcutaneous injection). However, Wegovy is also available as an oral medication.

• Dosing schedule: Both injectable Wegovy and Zepbound are taken once weekly. The Wegovy pill is taken once daily.

Here are some of the key similarities between Wegovy and Zepbound:

• Mechanism of action: Both medications work by improving the way your body processes sugar. They also help people feel full faster and for longer after eating.

• Safety profile: Both medications carry similar warnings and precautions.

• High cost: Both medications are expensive, with no generic alternatives available.

Wegovy vs. Zepbound dosing

Injectable Zepbound and Wegovy have similar dosing. They are both injected subcutaneously once a week, on the same day, into the abdomen, outer thigh, or back of the upper arm. The Wegovy pill, by contrast, is taken daily in the morning on an empty stomach.

With either the pill or the injection, the dosage starts low and then is gradually increased over a period of months until you reach your maintenance dosage.

Both the Wegovy and Zepbound pens come with a needle already attached and are meant for single use, so you dispose of the pen after each injection. Zepbound is also available in multi-dose vials, where the dose is drawn each week using a separate needle and syringe, as well as in multi-dose KwikPens, which also require a separate needle attachment.

Another difference between Zepbound vs. Wegovy is how long it takes to reach a maintenance dose. For Wegovy, it can take up to four months, whereas for Zepbound, it can take up to five.

The table below compares the typical dosing schedule for Wegovy and Zepbound:

Wegovy vs. Zepbound side effects

Since they’re both GLP-1s, Zepbound and Wegovy share many similar side effects, despite having different active ingredients. However, there are some differences. Here’s a list of the most common side effects of Wegovy and Zepbound that affected at least 2% of people in clinical trials:

Wegovy vs. Zepbound cost

Without insurance, Wegovy costs less than Zepbound. Here is a look at the typical prices for Zepbound vs. Wegovy:

• Wegovy has a list price of $1,349.02 per month. On Ro, cash payers can get the Wegovy pen for $199–$349 per month or the Wegovy pill for $149–$299 per month, depending on the dosage (see pricing details).

• Zepbound costs $1,086.37 per month (list price). On Ro, cash payers can get Zepbound multi-dose vials or KwikPens for $299–$449 per month, depending on the dosage (see pricing details).

In a 2025 study that directly compared tirzepatide and semaglutide injection for weight loss, tirzepatide outperformed semaglutide. After 72 weeks, participants taking tirzepatide experienced an average weight reduction of about 20%, while participants taking semaglutide averaged about 14% weight reduction.

Weight loss results can vary. Research suggests tirzepatide may produce greater weight loss than semaglutide, particularly at higher doses. For example:

• In clinical trials of Wegovy injection, participants with overweight or obesity experienced an average weight loss of 15% from their starting weight.

• In clinical trials of Zepbound, people taking lower doses experienced weight reduction similar to that seen with Wegovy. Those who took higher doses (10 mg and 15 mg) experienced an average weight loss of about 20% of their baseline weight.

Zepbound and Wegovy work best alongside lifestyle changes to achieve significant and lasting weight loss. A 2020 study suggests that adhering to an eating plan and exercise goals resulted in nearly 7% more weight loss than taking a GLP-1 medication alone. Following a nutritious eating plan and increasing physical activity may help maximize results.

The choice between these four medications is one to discuss with a healthcare provider, based on individual medical history and treatment goals. Here are some scenarios in which one medication may be more appropriate than another:

• Ozempic may be appropriate for people with type 2 diabetes and heart or kidney disease whose insurance covers it, or who prefer a needle-free option.

• Wegovy may be appropriate for people whose main goal is weight loss, particularly those who also have fatty liver disease or heart disease, or who prefer a needle-free option.

• Zepbound may be appropriate for people whose main goal is weight loss and/or who have obstructive sleep apnea (OSA).

• Mounjaro may be appropriate for people whose main goal is lowering blood sugar levels and whose insurance covers it.

A healthcare provider can help determine which weight loss medication may be most appropriate for a given patient's needs. An online telehealth service such as Ro Body can connect patients with a licensed healthcare provider who can prescribe these medications if appropriate.

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Ozempic, Wegovy, Zepbound, and Mounjaro are all FDA-approved medications with established efficacy for weight loss, type 2 diabetes, and other conditions.

• FDA-approved indications: Ozempic and Mounjaro are primarily approved for type 2 diabetes, while Zepbound and Wegovy are approved for weight loss.

• Dosing schedules: All four medications begin at a low dose and are gradually increased over several months, with Mounjaro and Zepbound taking the longest to reach a maintenance dosage and Ozempic taking the shortest.

• Method of administration: All four medications come in injectable forms administered once weekly. Ozempic and Wegovy are also available as a once-daily pill.

• Cost: Without insurance, Wegovy has the lowest list price among these medications, followed by Ozempic, then Zepbound, and finally Mounjaro.