In the world of medical weight loss, injectable medications are transforming the landscape.

These treatments offer new hope to individuals struggling with obesity or weight-related health conditions. Two of the most promising treatments making headlines are Wegovy and Mounjaro—both of which are proven to help patients lose weight. However, they work in different ways and come with distinct benefits and potential side effects. If you’re considering one of these options, I will explain the differences so that you understand how they compare as this is essential to making an informed decision.

In this blog, I will break down the key differences between Wegovy and Mounjaro, their mechanisms, efficacy, side effects, and what to expect during treatment, so you can determine which option might be best suited for you.

Understanding Wegovy and Mounjaro

What is Wegovy?

Wegovy (generic name: semaglutide) is an approved injectable medication specifically designed for chronic weight management. It is a higher-dose version of the drug Ozempic, which is used to treat type 2 diabetes. Wegovy belongs to a class of drugs known as GLP-1 receptor agonists. GLP-1 (glucagon-like peptide-1) is a hormone that is naturally released in the gut and helps regulate appetite and food intake.

When injected, Wegovy mimics the effects of GLP-1 by reducing hunger, slowing gastric emptying (the process by which food leaves your stomach), and helping people feel fuller for longer. The result is a decrease in overall caloric intake, leading to weight loss.

What is Mounjaro?

Mounjaro (generic name: tirzepatide) is a newer injectable medication that was initially developed to treat type 2 diabetes. Clinical trials have shown significant weight reduction in patients using Mounjaro, sparking widespread interest in its off-label use for obesity management.

Mounjaro works as a dual GIP and GLP-1 receptor agonist, meaning it mimics two different hormones—GIP (glucose-dependent insulinotropic polypeptide) and GLP-1—that regulate appetite, insulin production, and blood sugar control. By targeting both GIP and GLP-1 receptors, Mounjaro not only reduces hunger but also improves the body’s metabolic functions, potentially leading to even greater weight loss than GLP-1 agonists alone.

How Do They Compare?

While both Wegovy and Mounjaro are injectable medications that support weight loss, they have some important differences in terms of how they work, their effectiveness, and side effect profiles.

1. Mechanism of Action

• Wegovy: As a GLP-1 receptor agonist, Wegovy primarily acts on the hormone GLP-1. By slowing gastric emptying, suppressing appetite, and regulating blood sugar levels, it helps reduce caloric intake.
• Mounjaro: Mounjaro is a dual agonist that targets both GLP-1 and GIP receptors. GIP is another hormone involved in regulating appetite, fat metabolism, and insulin sensitivity. The dual action of Mounjaro can potentially offer more powerful effects on weight loss, as it targets two pathways related to appetite control and metabolism.

2. Efficacy: Which is More Effective?

Both medications have shown impressive results in clinical trials, but Mounjaro may have a slight edge in terms of overall weight loss.

• Wegovy: In clinical studies, patients using Wegovy lost an average of 15% of their body weight over 68 weeks. Some patients experienced even greater weight loss, especially when combined with lifestyle changes such as diet and exercise.
• Mounjaro: In recent trials, patients using Mounjaro lost an average of 15-22.5% of their body weight, depending on the dosage. This higher level of weight loss is likely due to its dual-action mechanism. Mounjaro’s results, particularly at higher doses, make it one of the most promising weight loss medications currently available.

3. FDA Approval for Weight Loss

• Wegovy: Approved specifically for weight loss in 2021 for adults with obesity (BMI ≥30) or overweight individuals (BMI ≥27) who have weight-related conditions like hypertension, type 2 diabetes, or high cholesterol.
• Mounjaro: Approved for weight loss and type 2 diabetes management, Mounjaro is widely due to its potent effect on reducing body weight
• 4. Dosage and Administration

Both medications are administered via a weekly subcutaneous injection, but their dosing differs:

• Wegovy: The starting dose is typically 0.25 mg once weekly, gradually increased to 2.4 mg per week over a period of about 5 months to minimize gastrointestinal side effects. After reaching the target dose, patients continue to use 2.4 mg weekly for maintenance.
• Mounjaro: Mounjaro is available in several doses (5 mg, 10 mg, and 15 mg), and the dose is gradually increased based on patient response and tolerability. Most patients are started on the lowest dose (5 mg weekly) and may eventually be increased to 10 mg or 15 mg depending on their needs.

5. Side Effects

Both Wegovy and Mounjaro have similar side effects due to their action on the gastrointestinal system, but their intensity and frequency may differ.

• Wegovy: Common side effects include nausea, vomiting, diarrhoea, constipation, and abdominal pain. Most side effects are mild and tend to diminish over time as the body adjusts to the medication. However, more serious side effects such as gallbladder problems and pancreatitis have been reported in rare cases.
• Mounjaro: Side effects are generally similar to Wegovy’s, with nausea, vomiting, and digestive issues being the most common complaints. However, some reports suggest that Mounjaro’s nausea may be more manageable due to its GIP component, which may help counterbalance the GLP-1-related gastrointestinal side effects. As with Wegovy, serious but rare side effects include pancreatitis and thyroid tumours (in animal studies).

Which Is Right for You?

Deciding between Wegovy and Mounjaro depends on several factors, including your medical history, weight loss goals, and response to treatment. Here are a few considerations:

• Wegovy may be ideal for individuals who want a medication specifically designed and approved for weight loss, especially if they have tried other weight loss methods without success. The established safety and efficacy profile make it a reliable option.
• Mounjaro might be a better fit for those seeking more aggressive weight loss, especially if other treatments have not provided sufficient results. Mounjaro’s dual mechanism of action makes it highly effective, particularly in individuals with metabolic conditions like diabetes.

Ultimately, it’s essential to discuss your individual health needs, lifestyle, and weight loss objectives. Both Wegovy and Mounjaro offer new pathways to meaningful, sustained weight loss when combined with a healthy diet, exercise, and behavioural changes.

Conclusion

Wegovy and Mounjaro represent two of the most exciting advancements in medical weight loss treatments today. Both injections offer a non-surgical, effective way to lose significant weight and improve overall health. While Wegovy is currently the more established choice, Mounjaro’s potential for even greater weight loss makes it a compelling alternative. By working closely with you at Rebanace Your Life, I can determine the best option for achieving your weight loss goals.