Recommended Dosage of Tirzepatide (Mounjaro) for Weight Loss
For weight loss, tirzepatide (Mounjaro) should be initiated at 2.5mg weekly for 4 weeks, then increased to 5mg weekly as the first maintenance dose, with further titration up to a maximum of 15mg weekly as tolerated. 1
Dosing Schedule and Titration
- Initial dose: 2.5mg once weekly for 4 weeks
- First maintenance dose: 5mg once weekly
- Dose escalation: Can be further titrated to 7.5mg, 10mg, 12.5mg, and a maximum of 15mg once weekly as tolerated
The American Diabetes Association guidelines recommend this stepwise approach to minimize gastrointestinal side effects while maximizing efficacy 1. Clinical trials have demonstrated that higher doses produce greater weight loss, with mean reductions of:
- 5mg weekly: 12.3% body weight reduction
- 10mg weekly: 18.7% body weight reduction
- 15mg weekly: 19.7-20.9% body weight reduction 2, 3
Efficacy for Weight Loss
Tirzepatide has demonstrated superior weight loss compared to placebo and other GLP-1 receptor agonists:
- In the SURMOUNT-1 trial, participants achieved 15.0% weight loss with 5mg, 19.5% with 10mg, and 20.9% with 15mg doses over 72 weeks, compared to only 3.1% with placebo 3
- 91% of participants on the 15mg dose achieved ≥5% weight loss
- 57% of participants on the 15mg dose achieved ≥20% weight loss 3
Administration Guidelines
- Administer subcutaneously in the abdomen, thigh, or upper arm
- Rotate injection sites with each dose
- Can be administered at any time of day, with or without meals 1
Side Effects and Management
The most common adverse effects are gastrointestinal:
- Nausea (31%)
- Diarrhea (23%)
- Vomiting (12%)
- Constipation (5%) 1
To manage these side effects:
- Start with the low dose (2.5mg)
- Titrate slowly
- Reduce meal size
- Avoid high-fat foods
- Limit alcohol and carbonated drinks 1
Monitoring Recommendations
- Monthly assessment during the first 3 months, then quarterly thereafter
- Early response indicator: achieving >5% weight loss after 3 months typically predicts better long-term outcomes 1
- Monitor for rare but serious adverse effects such as pancreatitis 1
Special Considerations
- For women using oral hormonal contraception: use or add a non-oral contraception method for 4 weeks after initiation and after each dose escalation 1
- Consider the 5-day half-life when planning for surgical procedures 1
- Be aware that discontinuation can lead to regaining one-half to two-thirds of lost weight within a year, highlighting the importance of long-term therapy 1
Combination with Lifestyle Modifications
For optimal results, combine tirzepatide with:
- Dietary modifications (Mediterranean or low-carbohydrate diet)
- Regular physical activity
- Behavioral support and counseling 1
This comprehensive approach maximizes weight loss and improvements in cardiometabolic risk factors.