What did SURMOUNT-1 show by dose?
Higher doses produced more loss, with diminishing gaps between 10 and 15 mg. SURMOUNT-1 randomized 2,539 adults with obesity, or overweight plus a related condition, and no diabetes to weekly tirzepatide or placebo for 72 weeks. The Zepbound label reports the results:
| Weekly dose | Average weight change at 72 weeks |
|---|---|
| Placebo | -3.1% |
| 5 mg | -15.0% |
| 10 mg | -19.5% |
| 15 mg | -20.9% |
For a 240-pound man, those percentages translate to about 36 pounds at 5 mg and about 50 pounds at 15 mg. That is arithmetic on an average, not a forecast.
What is the month-by-month pace in year one?
Fast early, then slower, then a plateau. The label includes the trial’s time course of observed averages. Reading that figure gives roughly this pace:
| Time on treatment | 5 mg | 10 mg | 15 mg |
|---|---|---|---|
| 1 month (week 4) | about -3% | about -3% | about -3% |
| 2 months (week 8) | about -6% | about -6% | about -6% |
| 3 months (week 12) | about -8% | about -8.5% | about -8.5% |
| 6 months (week 24) | about -11.5% | about -14% | about -14.5% |
| 9 months (week 36) | about -13.5% | about -17% | about -18% |
| 11 months (week 48) | about -15% | about -19% | about -20% |
| 14 months (week 60) | about -16% | about -20.5% | about -21.5% |
Values are read from the figure, so treat them as approximate. Two things stand out. For the first two months the curves overlap, because everyone starts on the same low doses. The doses separate from month three or four onward, as the higher-dose groups keep climbing.
Why do the doses look the same at first?
Because of the dose climb. Per the label, everyone starts at 2.5 mg weekly for four weeks, a starter dose that is not meant for maintenance, then steps up by 2.5 mg no sooner than every four weeks. In the trial, reaching the assigned dose took up to 20 weeks. A man aiming for 15 mg is on 5 mg or 7.5 mg for much of his first quarter. Your provider sets that pace based on how each step goes.
MedlinePlus notes that nausea, diarrhea, vomiting, constipation and decreased appetite are the common side effects, and they are the main reason a step gets held. A held step slows the early pace, which is usually a fair trade if it keeps you on treatment.
What shapes your own result?
Several things beyond the dose:
- Tolerance. Some men settle at 10 mg because 15 mg causes too much stomach upset.
- Eating and alcohol. The medicine reduces appetite; what you eat when you are hungry still counts.
- Strength training and protein. These decide how much of the loss is fat rather than muscle.
- Staying on it. In SURMOUNT-1, more people dropped out on placebo than on tirzepatide, but every dropout changes the math.
For context on staying the course, the SURMOUNT-4 trial gave everyone open-label tirzepatide for 36 weeks, during which they lost an average of 20.9%. Those switched to placebo then regained 14.0% over the next year, while those who continued lost another 5.5%.
Related question: how does semaglutide compare in the early months?
Semaglutide’s curve in its main trial was gentler, reaching about 6% at three months. We break that down in semaglutide weight loss in 3 months. Men who plateau on semaglutide sometimes ask about changing medicines; see switching from semaglutide to tirzepatide.
How Ultimate Male plans a first year on tirzepatide
At Ultimate Male, a year on tirzepatide starts with labs, a body composition analysis and a consultation with a PA-C or MD at the San Gabriel or Downey clinic. From there, the plan sets a realistic target for your dose and history, and check-ins measure fat and muscle rather than scale weight alone.
Read about the tirzepatide weight loss program and the tirzepatide medication guide for more detail, or see the wider medical weight loss program. Prices are quoted before you commit, and itemized receipts work for FSA or HSA claims. The free 10-minute call is the easiest way in.
