Mounjaro for Weight Loss

Mounjaro (tirzepatide) is not FDA-approved as a weight loss drug. Any use of Mounjaro for weight loss is off-label. The U.S. Food and Drug Administration limits Mounjaro’s approval solely to adults diagnosed with Type 2 diabetes to improve control of their blood sugar levels. Mounjaro is under review for approval as a weight loss medication.

However, the FDA has approved Eli Lilly’s Zepbound, another tirzepatide medication, for weight loss.

Mounjaro has been found effective for weight loss in clinical trials. Users achieved a total mean weight loss of 26.6% over 84 weeks.

Mounjaro and Ozempic are each being used off-label for weight loss. When comparing Mounjaro to Ozempic, studies show that Mounjaro is more effective for weight loss.

“If [a patient] is treated for diabetes and A1C is not controlled on Ozempic, I usually try to switch to Mounjaro,” Dr. Eldad Einav, board-certified cardiologist, obesity specialist and owner of weight loss practice myW8, told Drugwatch.

However, neither is FDA-approved for weight loss. Saxenda, Wegovy and Zepbound are the only GLP-1 drugs with FDA approval for weight loss.

How Long Does It Take To Lose Weight Using Mounjaro?

Mounjaro can help users lose weight over weeks, with trial results showing an average of 26.6% weight loss in 72 weeks. Studies have shown that the drug’s effectiveness increased with significant lifestyle changes.

A meta-analysis of 18,472 patients showed Mounjaro to be more effective than semaglutide options in as little as 12 weeks. Higher doses of tirzepatide resulted in greater weight loss, according to research presented at the Annual Meeting of the European Association for the Study of Diabetes in 2023.

Weight Loss Case Study: Barb Herrera

Mounjaro is part of the class of GLP-1 agonists, diabetes medications that also cause people to lose weight. Herrera started on Trulicity (dulaglutide) before switching to Mounjaro. These drugs have helped treat Barb Herrera’s diabetes. She blogs about her medical journey at HealthAtAnyCost.com.

“I’ve been on GLP-1s since 2022 and have been on Mounjaro for 6 months now,” Herrera told Drugwatch. “I’m down 197 pounds in 21 months.”

Of course, weight loss is not the only effect the drug has on patients’ health.

“I am on Mounjaro for Type 2 diabetes and my initial hemoglobin A1C was 9.0. On Mounjaro, it’s now in the non-diabetic range of 5.1. My diabetes is in remission,” Herrera said.

Mounjaro is only available by prescription. You can speak with your health care provider to see if it might be a fit for your specific needs.

Remember that Mounjaro is only approved to treat Type 2 diabetes. Since the FDA approved Zepbound for weight loss in 2023, doctors are more likely to prescribe it for that purpose over Mounjaro. The medical experts Drugwatch spoke with recommended against using Mounjaro for weight loss after Zepbound’s introduction and FDA approval.

With the rise of telehealth services in the U.S., many patients turn to online health providers for weight loss drug prescriptions. There are important considerations to keep in mind when taking this route.

Some users experience Mounjaro side effects, with the most common being gastrointestinal concerns.

“Side effects for all GLP-1 medications — and GLP-1/GIP for Mounjaro and Zepbound — are basically the same,” Herrera said. “Mainly gastrointestinal issues such as nausea, vomiting, constipation and diarrhea.”

Mounjaro also has a boxed warning due to the risk of thyroid C-cell tumors. Eli Lilly is facing Mounjaro lawsuits over claims that the drug has caused harm to patients, including severe gastrointestinal injuries such as drug-induced stomach paralysis and vomiting. Ozempic users cite similar claims of severe gastrointestinal injuries.

Though the FDA is currently evaluating the safe use of Mounjaro for weight loss, it does not have approval for this purpose. The potential risks of using the drug off-label may outweigh the benefits in your particular situation.

For that reason, doctors recommending tirzepatide for weight loss will most likely prescribe Zepbound. However, they may choose to prescribe Mounjaro off-label if there is a significant shortage of Zepbound.

Taking Mounjaro to lose weight is a personal decision that should involve the insight and advice of your primary care physician. Because of the potential for adverse side effects or risks associated with off-label use of a drug, you should only use Mounjaro off-label under the supervised use of your physician.