Short answer
Response to Zepbound varies, and in trials weight loss slowed and leveled off for most people. In the main trial, 85% to 91% lost at least 5% of body weight by week 72, so some did not. In a post hoc analysis, the median time to a plateau was about 24 to 36 weeks. A stall is a conversation for your prescriber, who sets your dose.
How much people lost in SURMOUNT-1
In SURMOUNT-1, adults without diabetes took Zepbound or placebo for 72 weeks alongside diet and activity counseling. Average weight loss was 15.0% on 5 mg, 19.5% on 10 mg and 20.9% on 15 mg, against 3.1% on placebo. The spread was wide. On 15 mg, 90.9% lost at least 5%, 70.6% lost at least 15% and 56.7% lost at least 20%. On 5 mg, those shares were 85.1%, 48.0% and 30.0%. So even on the top dose, roughly 3 in 10 people did not reach 15%.
People with type 2 diabetes lost less
In SURMOUNT-2, adults with type 2 diabetes lost 12.8% on 10 mg and 14.7% on 15 mg, against 3.2% on placebo, and 79.2% and 82.8% lost at least 5%. The label says weight fell with Zepbound regardless of age, sex, race, ethnicity, starting BMI and blood sugar status, but these are averages across groups. They cannot tell you how much you will lose, or why your own loss has slowed.
When weight loss levels off
A 2025 post hoc analysis by Lilly-affiliated researchers looked at 1,438 SURMOUNT-1 participants who stayed on treatment and lost at least 5%. A plateau meant less than 5% weight change over 12 weeks and every 12 weeks after. Median time to a plateau ran from 24.3 weeks in people with overweight to 36.1 weeks in the highest BMI groups, and about 88% to 90% had plateaued by week 72. Higher doses, younger age and female sex were linked to reaching it later. In the trial's 3-year extension, weight reduction was sustained.
What the label says about dose
The label starts everyone at 2.5 mg for 4 weeks, which is for starting treatment and not a maintenance dose, then 5 mg. The dose may rise in 2.5 mg steps after at least 4 weeks on each, to a maximum of 15 mg. It tells prescribers to consider treatment response and tolerability when choosing the maintenance dose. In the trials, escalation took up to 20 weeks, and results were measured after 72 weeks. Whether your stall is expected, and whether to change anything, is for your prescriber to decide.
Related questions
Should I lose weight on the 2.5 mg starting dose?
The label says the 2.5 mg dosage is for treatment initiation and is not approved as a maintenance dosage. It does not give an expected weight loss for that dose alone.
Is a plateau normal on Zepbound?
In a post hoc analysis of SURMOUNT-1, about 88% to 90% of participants who stayed on treatment and lost at least 5% had reached a plateau by week 72. It cannot tell you whether your plateau is expected.
What is the highest Zepbound dose?
The label sets 15 mg once weekly as the maximum dosage for all uses.
Read next
Sources
- Eli Lilly: Zepbound prescribing information, sections 2 and 14 (revised 08/2026)
- New England Journal of Medicine: Tirzepatide Once Weekly for the Treatment of Obesity, Jastreboff (2022)
- Clinical Obesity: Time to weight plateau with tirzepatide in SURMOUNT-1 and SURMOUNT-4, Horn et al. (2025)
- New England Journal of Medicine: Tirzepatide for Obesity Treatment and Diabetes Prevention, Jastreboff (2025)
Published 2026-10-07 · Last checked 2026-10-07
Educational content, not medical advice. Made for the United States.