From the FDA Drug Label
The mean baseline BMI was 32 kg/m2, 34 kg/m2, and 33 kg/m2 in the SURPASS-1, SURPASS-2, and SURPASS-4 trials, respectively. In the SURPASS-1 trial, monotherapy with MOUNJARO 5 mg, 10 mg and 15 mg once weekly for 40 weeks resulted in a change in body weight of -6.3 kg, -7.0 kg, and -7.8 kg, respectively. In the SURPASS-2 trial, treatment with MOUNJARO 5 mg, 10 mg, and 15 mg once weekly for 40 weeks resulted in a change in body weight of -7.6 kg, -9.3 kg, and -11.2 kg, respectively. In the SURPASS-3 trial, treatment with MOUNJARO 5 mg, 10 mg, and 15 mg once weekly for 52 weeks resulted in a change in body weight of -7.0 kg, -9.6 kg, and -11.3 kg, respectively. In the SURPASS-4 trial, treatment with MOUNJARO 5 mg, 10 mg, and 15 mg once weekly for 52 weeks resulted in a change in body weight of -5.0 kg, -8.4 kg, and -10.3 kg, respectively.
The recommended weight loss for MOUNJARO is not explicitly stated in the drug label. However, the clinical trials suggest that treatment with MOUNJARO can result in significant weight loss, with changes in body weight ranging from -5.0 kg to -11.3 kg over 40-52 weeks, depending on the dose and trial.
- The weight loss achieved with MOUNJARO 5 mg, 10 mg, and 15 mg was -6.3 kg, -7.0 kg, and -7.8 kg in the SURPASS-1 trial, respectively.
- The weight loss achieved with MOUNJARO 5 mg, 10 mg, and 15 mg was -7.6 kg, -9.3 kg, and -11.2 kg in the SURPASS-2 trial, respectively.
- The weight loss achieved with MOUNJARO 5 mg, 10 mg, and 15 mg was -7.0 kg, -9.6 kg, and -11.3 kg in the SURPASS-3 trial, respectively.
- The weight loss achieved with MOUNJARO 5 mg, 10 mg, and 15 mg was -5.0 kg, -8.4 kg, and -10.3 kg in the SURPASS-4 trial, respectively 1.
From the Research
Mounjaro (tirzepatide) is recommended for weight loss, with a typical reduction of 15-20% of initial body weight over 72 weeks of treatment, as supported by the most recent and highest quality study 2.
Key Points
- The medication works by mimicking two hormones—GLP-1 and GIP—that regulate blood sugar and appetite, helping patients feel fuller longer and eat less.
- Weight loss usually begins within the first few weeks of treatment and continues gradually throughout therapy.
- The medication follows a dose-escalation schedule, starting at 2.5mg weekly for 4 weeks, then increasing to 5mg, with potential further increases to 7.5mg, 10mg, 12.5mg, and 15mg based on response and tolerability.
- For optimal results, Mounjaro should be combined with a reduced-calorie diet and increased physical activity.
- Common side effects include nausea, diarrhea, and vomiting, which often improve over time as the body adjusts to the medication.
- Patients should maintain regular follow-ups with their healthcare provider to monitor progress and adjust treatment as needed.
Evidence Summary
- A 2025 study published in Diabetes, Obesity & Metabolism found that tirzepatide was associated with a significantly lower risk of all-cause mortality compared with bariatric metabolic surgery (BMS) 2.
- Another study published in 2023 in the International Journal of Obesity found that tirzepatide demonstrated significant weight loss effects, with 78.22% of patients achieving ≥5% weight loss, 55.60% achieving ≥10% weight loss, and 32.28% achieving ≥15% weight loss 3.
- A 2024 study published in Medical Principles and Practice found that tirzepatide treatment resulted in weight reductions of 5.0%, 14.9%, and 17.7% at different concentrations, compared to a sham group 4.
- A 2025 study published in Obesity Research & Clinical Practice found that tirzepatide treatment significantly enhanced weight loss and metabolic health in post-bariatric patients, regardless of surgery type or sex 5.