What is the dosing regimen for Mounjaro (tirzepatide) for weight loss?

Tirzepatide (Mounjaro) Dosing for Weight Loss

For weight loss in adults, tirzepatide (Mounjaro) should be started at 2.5 mg subcutaneously once weekly and gradually increased to a maximum of 15 mg weekly, with dose escalation every 4 weeks as tolerated. 1, 2

Initial Dosing and Titration Schedule

• Start with 2.5 mg subcutaneously once weekly for 4 weeks 1, 2
• Increase to 5 mg once weekly for 4 weeks 1, 2
• Increase to 7.5 mg once weekly for 4 weeks 1, 2
• Increase to 10 mg once weekly for 4 weeks 1, 2
• Increase to 15 mg once weekly (maximum dose) 1, 2

Efficacy Data

• Tirzepatide demonstrates superior weight loss compared to other GLP-1 receptor agonists:
  • 15 mg weekly: 20.9% weight loss from baseline (vs. 3.1% with placebo) 1
  • 10 mg weekly: 12.8% weight loss from baseline 1
  • Tirzepatide showed 20.2% weight loss compared to 13.7% with semaglutide in head-to-head trials 3

Monitoring and Assessment

• Evaluate efficacy and safety monthly for the first 3 months, then quarterly thereafter 1
• Consider continuing therapy if ≥5% weight loss is achieved after 3 months of treatment 1
• Consider discontinuation if <5% weight loss after 3 months at maximum tolerated dose 1

Side Effects and Safety Considerations

• Most common adverse effects are gastrointestinal (mild to moderate severity) 2:
  • Nausea (31%)
  • Diarrhea (23%)
  • Vomiting (12%)
  • Constipation (5%) 1
• Side effects typically occur during dose escalation period 2
• Monitor for delayed gastric emptying, which may affect absorption of other oral medications 1
• Advise females using oral contraceptives to switch to non-oral contraceptive methods 1
• Black box warning: Risk of thyroid C-cell tumors in rodents (human relevance not determined) 1

Contraindications

• Personal or family history of medullary thyroid carcinoma 1
• Multiple endocrine neoplasia type 2 1
• Pregnancy (contraindicated in women who are or may become pregnant) 1

Practical Considerations

• Administered via single-dose prefilled pens 4
• Typical monthly cost: $1,272 (AWP) or $1,017 (NADAC) for 30-day supply 1
• Insurance coverage may be limited as tirzepatide was initially approved for diabetes management 1
• Gradual dose escalation helps minimize adverse events 1, 2

Additional Benefits Beyond Weight Loss

• Improvements in waist circumference (18.4 cm reduction with tirzepatide vs. 13.0 cm with semaglutide) 3
• Significant improvements in health-related quality of life measures 5
• Greater improvements in quality of life observed with greater weight loss thresholds 5
• Improvements in cardiometabolic measures 2

By following this structured dosing regimen and monitoring protocol, tirzepatide can provide substantial and sustained weight reduction in adults with overweight or obesity.