Why Am I Not Losing Weight on Wegovy, Ozempic, Mounjaro or Zepbound?

Wegovy starts at 0.25 mg and does not reach the 2.4 mg maintenance dose until week 17 at the earliest, so the first months run on doses below the one tested for weight loss.2 The label steps the dose up every 4 weeks: 0.25 mg, 0.5 mg, 1 mg, 1.7 mg, then 2.4 mg.2 If a step is not tolerated, the label lets prescribers delay escalation by 4 weeks.2

Four other points from the Wegovy label:

• Some people respond less. In the main trial, 83.5% on Wegovy 2.4 mg lost at least 5% by week 68, so 16.5% did not.2
• Type 2 diabetes changes the numbers. Average loss at week 68 was 14.9% in adults without diabetes and 9.6% in adults with type 2 diabetes.2
• Missed doses reset the climb. If 2 or more doses in a row are missed, the label tells prescribers to restart the step-up at a lower dose.2
• There is a higher dose. Adults who tolerate 2.4 mg for at least 4 weeks and need more weight reduction may move to 7.2 mg, sold as Wegovy HD.2

The Wegovy pill starts at 1.5 mg for 30 days and reaches the 25 mg maintenance dose on day 91.2 The label also sets strict rules: take it on an empty stomach in the morning with up to 4 ounces of water, then wait at least 30 minutes before eating, drinking or taking other pills.2 In a study in the label, semaglutide absorption was higher with a longer wait after the dose.2 See our Wegovy pill guide.

Ozempic is approved for type 2 diabetes, not weight loss, and its doses and results are lower than Wegovy's.4 Ozempic's maximum is 2 mg weekly, while Wegovy's maintenance dose is 2.4 mg and its top dose 7.2 mg.4,2

In the Ozempic label's 30-week monotherapy trial, people lost 3.8 kg on 0.5 mg and 4.7 kg on 1 mg on average, against 1.2 kg on placebo.4 That is a much smaller effect than Wegovy's 14.9% average at week 68.2 The comparison of Ozempic vs Wegovy covers the differences in detail.

Tirzepatide starts at 2.5 mg, a dose the labels say is for starting treatment and not for maintenance, and in SURMOUNT-1 about 1 in 5 adherent participants had not lost 5% by week 12.1,3,5

The SURMOUNT-1 analysis is useful for anyone worried in the first months:5

• 18% of participants were late responders, with less than 5% loss at week 12.
• 70% of those late responders reached 5% by week 24.
• 90% of them reached 5% by week 72.
• Their mean time to 5% loss was 24.8 weeks.

Dose matters too. Average loss at week 72 was 15.0% on Zepbound 5 mg, 19.5% on 10 mg and 20.9% on 15 mg.1 Even on 15 mg, 9.1% did not reach 5% loss.1 In adults with type 2 diabetes, average loss on 15 mg was 14.7%.1 Mounjaro contains the same drug and follows the same 2.5 mg step-up schedule.3 Our guide to how long Zepbound takes to work has the week-by-week timeline.

Compounded tirzepatide is not FDA-approved, and the FDA does not review compounded drugs for safety, effectiveness or quality before they are sold.9 The trial results above were measured with the brand-name drugs.

Dose accuracy is a known problem. The FDA has received reports of dosing errors with compounded semaglutide, including confusion between units, milliliters and milligrams.10 The same number of units holds a different dose in vials of different strengths. Check the concentration on your vial with your pharmacist, and use our dose converter to do the math. See compounded tirzepatide and tirzepatide units to mg. If you are choosing a pharmacy-made source, compounded tirzepatide vs Zepbound sets out what differs from the brand.

Every weight-loss treatment eventually reaches a plateau, because the body raises appetite as weight falls. A modeling study from the National Institutes of Health found that semaglutide and tirzepatide weaken that appetite feedback, which lets weight loss continue longer before it levels off.7 Diet restriction alone did not weaken it in the model.7

A plateau after months of loss is expected. It is different from not losing weight in the first weeks, which is usually about dose and time.

The labels do not list weight gain as an expected effect of Ozempic, so weight gain on treatment is something to raise with your prescriber. In the Ozempic monotherapy trial, average weight went down, not up.4

Weight does return when treatment stops. In the STEP 1 extension, people who stopped semaglutide 2.4 mg regained two-thirds of their lost weight within a year.8 Long gaps between doses also count: the Ozempic label says semaglutide stays in circulation for about 5 weeks after the last dose.4 See how long GLP-1s stay in your system.

The labels leave the maintenance dose to the prescriber, based on response and tolerability.1,2 Useful questions:

• Am I on a maintenance dose yet, or still stepping up?
• Has my escalation been delayed or restarted?
• Is a higher dose an option for me?
• Could my other medicines or conditions affect my result?
• Is my compounded dose measured the way the pharmacy intended?

Why am I not losing weight on Zepbound 5 mg? 5 mg is the first maintenance dose. In the main trial, average loss on 5 mg was 15.0% at week 72, measured after the full trial period.1

Why am I not losing weight on Mounjaro 15 mg? 15 mg is the highest tirzepatide dose. In the Zepbound trial, 9.1% of people on 15 mg did not reach 5% loss.1 Mounjaro is approved for type 2 diabetes, where average losses were lower.3,1

How long before a GLP-1 counts as not working? The labels do not set a cutoff. In SURMOUNT-1, most slow starters reached 5% loss by week 72.5

Is it normal to lose less than other people? Yes. Trial results are averages. In STEP 1, 50.5% of semaglutide participants lost at least 15%, so about half lost less.6

If cost limits your dose or format, our GLP-1 rankings compare programs, and Wegovy vs Zepbound shows how the two strongest drugs differ. For brand-name pricing, see Zepbound cost.

This article is for information only and is not medical advice. Do not change your dose, skip doses or stop a GLP-1 without talking to your prescriber. These are prescription drugs with real risks and side effects.