Maintenance Dosing After Achieving BMI 22.66 on Tirzepatide 15 mg
You should continue tirzepatide at your maximum tolerated dose (15 mg) for long-term weight maintenance, as discontinuation leads to substantial weight regain while continued treatment maintains and even augments initial weight loss. 1
Evidence for Continued Treatment
The SURMOUNT-4 trial provides the strongest evidence for your situation. When participants who achieved significant weight loss on tirzepatide were randomized to either continue treatment or switch to placebo:
- Continuing tirzepatide maintained weight loss with an additional 5.5% reduction over 52 weeks
- Switching to placebo resulted in 14% weight regain (difference of 19.4% between groups)
- 89.5% of those continuing tirzepatide maintained at least 80% of their initial weight loss, compared to only 16.6% on placebo 1
The more recent SURMOUNT-MAINTAIN trial (2026) reinforces this, showing that continuing at maximum tolerated dose (MTD) resulted in 21.9% total weight loss from baseline, versus only 9.9% with placebo 2.
Why Not Reduce the Dose?
While you might consider dose reduction given your now-normal BMI, the evidence suggests this is suboptimal:
- Reducing to 5 mg tirzepatide resulted in intermediate outcomes (16.6% total weight loss) but still required rescue therapy in 25% of participants who regained ≥50% of lost weight 2
- Continuing MTD required rescue therapy in only 8% of participants 2
- Low-dose studies (2.5-5 mg) show comparable short-term results but lack long-term maintenance data in your specific context 3, 4
Clinical Considerations
Obesity is a chronic disease requiring long-term treatment. 5 Your BMI of 22.66 represents successful treatment, not a reason to discontinue. The guideline framework emphasizes that:
- Tirzepatide provides superior weight loss benefits (mean 8.63 kg greater than alternatives) 5
- For patients at lower cardiovascular risk (which you likely are now with normal BMI), the weight maintenance benefits justify continued therapy 5
- Treatment should balance weight maintenance against gastrointestinal side effects (mostly mild-to-moderate) 6, 1
Practical Algorithm
Continue 15 mg weekly unless:
- You develop intolerable side effects → consider 10 mg if that was your prior MTD
- You have cardiovascular disease → ensure SGLT-2 inhibitor is added per guidelines 5
- Cost/access becomes prohibitive → 5 mg is better than discontinuation 2
Monitor for:
- Weight stability (expect maintenance with possible additional 3-5% loss)
- Gastrointestinal symptoms (usually diminish after initial titration phase) 1
- Any weight regain >5% → signals need to reassess adherence or dose
Common Pitfall to Avoid
Do not discontinue therapy simply because you've reached a "goal weight." This is the most common error. The evidence unequivocally shows that obesity treatment requires ongoing medication to maintain benefits, similar to managing hypertension or diabetes. Stopping treatment will likely result in regaining most of the lost weight within one year 1.