Recently, Mounjaro and Zepbound have become hot topics among people looking to lose weight and improve their overall health. While primarily known for the treatment of diabetes, Mounjaro is starting to gain recognition for its potential to curb appetites and slow digestion, both things Zepbound has a strong reputation for achieving. Since both medications are produced by a single manufacturer, a common question we get is whether Mounjaro and Zepbound are the same. In this article, we define Mounjaro and Zepbound, highlight the key differences between these two popular medications, and share a few things they have in common.

What Is Mounjaro?

Manufactured by Eli Lilly, Mounjaro has been FDA-approved to treat Type 2 diabetes since May 2022. As a GLP-1 receptor agonist and a glucose-dependent insulinotropic polypeptide (GIP) receptor, Mounjaro imitates the naturally occurring hormones that tell your body when you're full. While Mounjaro isn't approved as a weight loss drug at this time, it still decreases appetite and slows down digestion, which can help patients shed excess pounds. Patients can self-administer Mounjaro at home as a subcutaneous injection once per week.

What Is Zepbound?

In November 2023, the FDA approved Zepbound as a weight loss treatment for adults. Also manufactured by Eli Lilly, this medication is growing in popularity and is available via mail-order and through retail pharmacies with a prescription. To administer Zepbound, patients self-inject the drug once a week, which is similar to most diabetes medications. It contains the same amount of the active ingredient tirzepatide as its predecessor, Mounjaro. This ingredient accomplishes two things. First, it curbs appetite, reducing how much food patients consume. Second, it breaks down sugars and fats by replicating the hormones our bodies naturally release after eating.

Are Mounjaro and Zepbound the Same?

As you've conducted your own research about weight loss medications, you might have wondered whether Mounjaro and Zepbound are the same. The answer: it's complicated. While the drugs themselves are identical in their chemical makeup, there are some key differences in how the FDA regulates each of them. Let's take a closer look at how Mounjaro and Zepbound stack up when compared side by side:

Clinical Trials and Effectiveness

Since Mounjaro and Zepbound both contain the same amount of tirzepatide, these two medications are essentially the same—they just have different names and uses. While both medications can treat Type 2 diabetes and obesity, the clinical trials for each drug focus on different areas of effectiveness.

Most of the studies conducted on Mounjaro focus on its effectiveness in treating diabetes first. Some trials layer in additional studies to assess whether Mounjaro can help patients with diabetes lose weight more effectively than semaglutides like Ozempic. A study published in June 2022 reveals that between 87% and 97% of participants taking Mounjaro experienced a decrease in both their A1C levels and weight. Furthermore, participants reached their A1C goals approximately one month sooner than people taking a one-milligram dose of an injectable semaglutide.

One of the reasons Zepbound is such a popular new weight loss medication is that the drug has performed very well in clinical trials. Recently, the FDA shared a study revealing Zepbound's effectiveness in helping adults with diabetes lose weight. The results show that the participants who took Zepbound for 17 months saw their body weight decrease by 18% on average when compared to participants who received a placebo.


Patients often tolerate tirzepatide-based medications like Mounjaro and Zepbound better than semaglutide-based drugs like Ozempic and Wagovy, which are also commonly used for weight loss and diabetes. Furthermore, tirzepatides outperform semaglutides in clinical trials, making it easier for patients to lose more weight in less time. If you're considering bariatric surgery to lose weight, opting for a tirzepatide like Zepound may be a less invasive choice to achieve a healthier lifestyle.

Side Effects

Since Mounjaro and Zepound are the same drug with different labels, the same side effects are associated with each medication. When patients begin taking Zepbound, Eli Lilly notes they may experience gastrointestinal issues. The following common side effects typically clear up over time with continued use:

  • Constipation.
  • Vomiting.
  • Heartburn.
  • Tiredness.
  • Hair loss.
  • Injection site reactions.
  • Diarrhea.
  • Nausea.
  • Stomach pain.
  • Indigestion.
  • Allergic reactions.

Other side effects that are less common, but should be taken very seriously, include depression and suicidal thoughts, pancreatitis, kidney and gallbladder issues, changes in vision, and low blood sugar. If you experience any of these symptoms, consult with your doctor immediately.


As previously mentioned, the FDA has only approved Mounjaro for use in patients with Type 2 diabetes. People with Type 1 diabetes should not take Mounjaro. Maintaining a balanced diet and exercise routine is key to achieving decreased A1C levels and weight loss while using this medication and can help patients remain healthy long-term. Studies indicate that patients using DPP-4 (dipeptidyl peptidase-4) inhibitors like Januvia or sitagliptin should not start taking Mounjaro.

While Zepbound is a very effective medication for weight loss, it's not for everyone. At this time, doctors can only prescribe Zepbound to patients who are considered obese or overweight and dealing with other weight-related health issues, such as diabetes or heart complications. Eli Lilly does not recommend Zepbound for patients with a family or personal history of medullary thyroid cancer or multiple endocrine neoplasia syndrome type 2. Although the FDA hasn't determined whether Zepbound poses the same risk to humans, studies show the medication produces thyroid C-cell tumors in rats.

Ready To Take the Next Step on Your Weight Loss Journey?

Whether Mounjaro or Zepbound can help you achieve your health goals may depend on whether you have Type 2 diabetes or an additional weight-related condition. If you're interested in learning more about tirzepatides, speak with your primary care physician or schedule a consultation with our world-class medical team today. As South Florida's premier anti-aging and wellness practice, we offer several weight loss programs to help people replenish their lives, including tirzepatides like Zepbound, semaglutide peptides, and naltrexone. We also provide a comprehensive nutrition program so you can achieve your optimal metabolic health and maintain it moving forward.