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Mounjaro weight loss: How tirzepatide helps you lose weight

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Many drugs out there help in the battle against type 2 diabetes and the critical obesity epidemic, but one has made a grand entrance and stolen the show. Last year, in May 2022, the U.S. Food and Drug Administration (FDA) approved a new drug called tirzepatide under the Mounjaro® brand name. This new medication is the first and only dual-targeted treatment with a glucose-dependent insulinotropic polypeptide (GIP) receptor agonist and glucagon-like peptide-1 receptor agonist (GLP-1) for adults with type 2 diabetes. 

Combining GIP and GLP-1 receptor agonists can have a more significant impact on metabolic dysregulation. Another benefit of the GIP and GLP-1 receptor agonist is that GIP has been shown to decrease food intake and regulate energy expenditure, so it aids in greater weight loss. 

Manufactured by Eli Lilly and Company, Mounjaro has also shown impressive trial results in those with obesity and overweight. Although tirzepatide isn’t FDA-approved for weight loss yet, doctors can prescribe Mounjaro off-label for weight loss. Learn more about how this drug works as a diabetes treatment and how it can support sustainable weight loss.

What is Mounjaro?

Mounjaro (tirzepatide) is a once-weekly injectable medication that helps lower blood glucose levels. It’s much like popular GLP-1 medications such as the diabetes medication Ozempic® or the weight-loss drug Wegovy®, manufactured by competitor Novo Nordisk. However, Mounjaro is in a drug class all its own because it’s a dual-targeted treatment. 

It’s currently indicated for those patients with type 2 diabetes, but health care professionals can prescribe Mounjaro for weight loss off-label. For best weight loss results, Mounjaro should accompany healthy lifestyle changes—like diet and physical activity.

Although it’s not an obesity drug, Mounjaro (tirzepatide) just received a “fast track designation” from the FDA for treating overweight and obesity. When the FDA fast-tracks a drug, it means the regulators expedite the review of the drug because it treats a serious condition and has an “unmet need.” So, Mounjaro may soon not only be FDA approved as a diabetes medication but as a new weight-loss drug as well.

Why are obesity doctors excited about Mounjaro weight loss?

The findings of a clinical trial on tirzepatide weight loss showed that participants dropped up to 22.5% of their total body weight. Those are impressive stats, given that people taking many existing FDA-approved medications for obesity usually lose 5% to 15% of their total body weight. 

Eli Lilly released preliminary results from its SURMOUNT-1 clinical trial in April 2022. Participants with obesity or those with excess weight – a body mass index (BMI) of 27 or greater—who had at least one other comorbidity (but not diabetes) had  weight reductions of up to 52 pounds during the 72-week Mounjaro weight-loss trial. 

Mounjaro weight loss varied by dose. Study participants on a 5 mg dose of tirzepatide for weight loss experienced an average weight loss of 35 pounds or 16% of their body weight. Those on a 10 mg dose lost an average of 49 pounds or 21.4% of their body weight. 

On the highest dose—15 mg—people on tirzepatide lost an average of 52 pounds or 22.5% of their body weight. On the other hand, the placebo group lost just five pounds or 2.4% of their body weight over that same amount of time.

The randomized, double-blind tirzepatide weight-loss clinical trial included 2,539 participants throughout the U.S., Argentina, Brazil, China, India, Japan, Mexico, Russia, and Taiwan, with a mean baseline body weight of 231 pounds. All those randomly placed in the Mounjaro (tirzepatide) study began with a 2.5 mg weekly dose. They then underwent a dose-escalation period that increased by 2.5 mg every four weeks until they reached a target dose of 5, 10, or 15 mg.

While the FDA approved Mounjaro (tirzepatide) to treat type 2 diabetes, doctors specializing in obesity are particularly excited about this medication given the preliminary SURMOUNT-1 results. 

“As a board-certified obesity specialist, I believe that Mounjaro (tirzepatide) has the potential to be a game-changer in the treatment of obesity for certain patients who may not have responded to other medicines,” says Found’s chief of Medical Affairs Rekha Kumar, MD, MS. “A medication with this efficacy gives hope to patients who have run out of existing medication options because the mechanism of Mounjaro (tirzepatide) is unique. We are excited about the possibility of adding Mounjaro (tirzepatide) to the broad toolkit of medications Found clinicians already use to provide the best care possible to each Found member.”

How does Mounjaro work for weight loss?

As mentioned above, Mounjaro works much like other meds in the GLP-1 class, but it has the additional benefit of acting on not just one hormone but two. So, unlike its predecessors, which have been very effective but only mimic one hormone, Mounjaro acts on two incretin hormones, which can make it more effective.

In their April 2022 press release, Eli Lilly explained why this dual mechanism is so important. They detailed that the GIP hormone receptor agonist complements the GLP-1 hormone receptor agonist in a novel way. In addition, the release noted that obesity “is a chronic, progressive disease caused by disruptions in the mechanisms that control body weight, often leading to an increase in food intake and/or a decrease in energy expenditure.” 

The release said, “GIP has been shown to decrease food intake and increase energy expenditure, resulting in weight reductions, and when combined with GLP-1 receptor agonism, may result in greater effects on markers of metabolic dysregulation such as body weight, glucose and lipids.” Meaning the incretin hormones work together to help maintain weight loss by regulating blood glucose levels or appetite and helping your body lose more body fat.

But what are incretin hormones?

After eating, your gut naturally releases incretin hormones—the two primary hormones are GIP and GLP-1.  These hormones help regulate the insulin the pancreas releases to keep blood sugar levels under control effectively. But those who have overweight or obesity can become insulin resistant—meaning their body doesn’t respond to the hormone’s signaling—which results in too much glucose in the blood. Insulin resistance can lead to type 2 diabetes, weight gain, and elevated blood sugar levels. 

More than that, the GLP-1 incretin hormone helps food digestion happen more slowly, often called gastric or stomach emptying, causing you to feel fuller longer.

How to use the Mounjaro pen?

The Mounjaro pen automatically injects the medication into your body through a hidden needle. When you press the button on the Mounjaro pen, the needle enters your skin and retracts when the injection is complete. 

You use the Mounjaro pen once weekly on a day that’s best for you. You can inject the medication into your upper arm, upper thigh, or abdominal area.

You must keep your Mounjaro refrigerated (between 36°F to 46°F) to maintain its efficacy. Once used, dispose of the single-dose pen in an FDA-cleared sharps container. If no sharps container is available, the Mounjaro site says to use a household container that is “heavy-duty plastic with a puncture-resistant lid” and “upright, stable, leak resistant, and properly labeled to warn of hazardous waste.”

What is the Mounjaro dosage for weight loss?

Health care professionals recommend all patients begin their Mounjaro weight loss journey at 2.5 mg to see how well their body tolerates it and then increase the dose from there. It’s essential to follow your health care provider's instructions. 

Here is the recommended Mounjaro dose for weight loss:

First four weeks: 2.5 mg weekly

Second four weeks: 5 mg once weekly

Third four weeks: 7.5 mg once weekly

Fourth four weeks: 10 mg once weekly

Fifth four weeks:  12.5 mg once weekly

Sixth four weeks: 15 mg once weekly (maximum dose)

How could Mounjaro (tirzepatide) help you lose weight?

Like similar GLP-1 medications, Mounjaro (tirzepatide) is an injectable medication used once weekly that aids in controlling blood sugar levels that may also support weight loss.

GLP-1 receptor agonists seem to aid in weight loss in two key ways. First, they cause the stomach to empty more slowly, so you feel satisfied with less food. This slowing helps reduce caloric intake. Second, the GLP-1 receptor agonists appear to reduce appetite and hunger, which can help you make nutritional choices that better align with your goals.

The biological changes from GLP-1 medications may also help reduce your set point weight—the weight your body strives to maintain due to hormones, biology, and surroundings. Tirzepatide, like GLP-1 medications used for weight loss—sometimes off-label—such as Ozempic, Saxenda®, Trulicity®, Rybelsus®, Wegovy®, and Victoza®, may help you lose weight and keep it off long-term.

The novel thing about tirzepatide is it also works on GIP receptors. When you eat food, the GIP hormone stimulates insulin. But when your blood sugar falls, they stimulate glucagon secretion. Controlling these processes can help support weight loss beyond what GLP-1 medications and lifestyle changes alone can do.

When will Mounjaro be approved for weight loss?

Is Mounjaro FDA approved for weight loss? Not yet, but the FDA has approved Mounjaro (tirzepatide) as a type 2 diabetes drug. And Eli Lilly, the manufacturer, is expected to file for FDA approval for its use in adults with obesity and overweight in 2023. 

Novo Nordisk, the manufacturer of Wegovy, took a similar path. It got FDA approval for the GLP-1 RA Ozempic (semaglutide) to treat type 2 diabetes before getting Wegovy, the same drug at a higher dosage, approved for weight management.

Although FDA approval of Mounjaro for weight loss is still pending, there may be some cases where Found can prescribe diabetes medications, like Mounjaro, off-label for weight loss, before its FDA approval for weight management. Additionally, the FDA is expediting the review process to approve Mounjaro for weight loss (expected summer 2023).

What are the tirzepatide side effects?

The most common side effects of Mounjaro (tirzepatide) are:

  • constipation

  • decreased appetite

  • diarrhea

  • indigestion

  • nausea

  • stomach pain

  • vomiting

Like most GLP-1 receptor agonists, tirzepatide has an FDA-mandated boxed—or black box—warning for patients with a personal or family history of medullary thyroid cancer or who have multiple endocrine neoplasia syndrome type 2. They should not take tirzepatide for weight loss or other treatments.

How much does Mounjaro cost?

Because Mounjaro is so new, many insurance companies don’t cover it yet. According to Lilly’s list price, Mounjaro costs $1,023.04 per four-week fill. Lilly note, “the amount you pay will largely depend on your prescription drug insurance plan.”

That means that one 28-day fill will be upward of $1,000 without insurance. Check with your insurance company to see if they cover Mounjaro. Another option is the Mounjaro Savings Card program by Eli Lilly. With this, you may pay as little as $25 for a one-month prescription if you qualify, but you must have commercial health insurance. Learn more about the Mounjaro Savings Card and more here.

Will Found prescribe tirzepatide for weight loss?

You may be asking yourself, "can I get mounjaro for weight loss from Found?" Found offers a broad toolkit of medications and distinct treatment pathways to help people with obesity and excess weight achieve sustainable weight loss. Our medical health care providers will assess a member's unique health care needs and prescribe medically appropriate treatments, which may include Mounjaro or a GLP-1 medication.

Found offers a science-backed approach to weight care based on your unique biology, psychology, lifestyle, and prescription medication needs.

To start your journey with Found, take our quiz.


Access to GLP-1s prescriptions is now available as part of Found's weight-loss program. While GLP-1s are effective for weight loss, they are not clinically appropriate for everyone. Eligibility for a GLP-1 is based on a thorough evaluation of medical history, eating behavior, lab work, and insurance coverage. If a GLP-1 is not appropriate or affordable for you, Found providers can help determine if another effective medication is.

About Found

Found is among the largest medically-supported weight care clinics in the country, serving more than 200,000 members to date. To start your journey with Found, take our quiz.

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