Zepbound has a short dose list, and its label is specific about what each dose is for: one dose starts treatment, three are maintenance doses, and one of those is the ceiling. Everything about when you move between them belongs to your prescriber, who weighs how well the drug is working and how you feel on it [1]. The brand itself is profiled in Zepbound.
The highest Zepbound dose is 15 mg a week
Zepbound's label caps the dose at 15 mg once a week, and that cap is the same for every use. In the label's words, “The maximum dosage of ZEPBOUND for all indications is 15 mg injected subcutaneously once weekly” [1].
Zepbound is approved for two things: long-term weight reduction in adults with obesity, or with overweight plus at least one weight-related condition, and moderate to severe obstructive sleep apnea in adults with obesity. Neither use goes above 15 mg, so a higher number quoted for a tirzepatide product online isn't coming from this label. Compounded tirzepatide is a separate product with no FDA-approved dose list of its own; its starting-dose questions are covered in the compounded tirzepatide starting dose guide.
The lowest dose, 2.5 mg, is a starting dose only
The label starts every patient at 2.5 mg once a week, and it's clear that this dose isn't meant to be where you stay. “The 2.5 mg dosage is for treatment initiation and is not approved as a maintenance dosage” [1].
The label ties its slow start to the stomach. It says to follow its dose increases “to reduce the risk of gastrointestinal adverse reactions” [1]. The label says most nausea, vomiting and diarrhea occurred during dose escalation and decreased over time. That pattern does not establish constipation’s duration or mean every symptom follows a dose increase. The full picture is in Zepbound side effects and how long they last.
Some programs sell tirzepatide at doses below the label's 2.5 mg start, often called microdosing. The cited pivotal trials do not establish the benefits of that approach, and it is outside the labeled dosing schedule. The evidence gap is laid out in microdosing tirzepatide.
Starting and maintenance doses serve different roles
Here's every dose the label names and the role it gives each one. The table doesn't tell you when to change doses, because that timing is your prescriber's call, made at your visits.
| Weekly dose | Role on the label | Weight reduction | Obstructive sleep apnea |
|---|---|---|---|
| 2.5 mg | Starting dose only; “not approved as a maintenance dosage” | Start | Start |
| 5 mg | Maintenance dose | Yes | No |
| 10 mg | Maintenance dose | Yes | Yes |
| 15 mg | Maintenance dose and the maximum for every use | Yes | Yes |
Source: Zepbound prescribing information, sections 2.1–2.2 [1]. Zepbound is also made in 7.5 mg and 12.5 mg strengths; the label doesn't name either as a maintenance dose.
Maintenance doses differ for weight loss and sleep apnea
For weight, the maintenance dose is 5, 10 or 15 mg once a week. For obstructive sleep apnea, it's 10 or 15 mg [1]. That's the main way the two uses differ on paper: a 5 mg maintenance dose is an option for weight loss but not for sleep apnea.
The label doesn't pick one maintenance dose for everyone. It tells prescribers to “consider treatment response and tolerability when selecting the maintenance dosage,” and adds: “If patients do not tolerate a maintenance dosage, consider a lower maintenance dosage” [1]. So going down is part of the plan, not a failure. If a higher dose makes you miserable, that's a conversation to have with your prescriber rather than something to tough out alone.
Higher doses brought more weight loss, and a little more nausea
In SURMOUNT-1, 2,539 adults with obesity or qualifying overweight, without diabetes, were randomized to 5, 10 or 15 mg a week, or placebo, for 72 weeks. 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 [3]. The trial was supported by Eli Lilly, which makes Zepbound.
The listed nausea and discontinuation percentages differ across dose groups, without a uniform stepwise pattern for every reaction. Nausea was about as common on 10 mg as on 15 mg, and while more people stopped for side effects at higher doses, the gap between 10 and 15 mg was small.
| Weekly dose | Average weight loss at 72 weeks (SURMOUNT-1) | Nausea (label pool) | Stopped for side effects (label pool) |
|---|---|---|---|
| 5 mg | 15.0% | 25% | 4.8% |
| 10 mg | 19.5% | 29% | 6.3% |
| 15 mg | 20.9% | 28% | 6.7% |
| Placebo | 3.1% | 8% | 3.4% |
Weight loss comes from SURMOUNT-1 alone [3]. Nausea and stopping rates come from the label's pool of two weight trials [1], so the groups are not identical. The row does not estimate a single person’s benefit-risk tradeoff or represent one matched trial analysis.
None of this makes the top dose the right one for you. Plenty of people in SURMOUNT-1 lost a lot of weight at 5 or 10 mg, and the label explicitly allows staying lower if a higher dose isn't tolerated. Constipation actually ran a little lower at higher doses in the label pool; the per-symptom detail is in does Zepbound cause constipation.
Zepbound is taken once a week, at any time of day
Zepbound is a once-weekly medicine. The label says it's given “once weekly at any time of day, with or without meals” [1]. That answers the empty-stomach question: the label has no fasting rule for Zepbound, and your prescriber sets your schedule.
Semaglutide tablets are a different story with their own label rules, covered in oral semaglutide. How to inject, and what to do about a late or early dose, comes from your prescriber, your pharmacist and the Instructions for Use that come with your prescription.
Zepbound also stays in your body for a while. The label puts its half-life at “approximately 5-6 days” [1], which describes its elimination profile. It does not establish an individual duration of symptom relief or side effects.
The label sets no time limit on Zepbound
There's no point on the label where Zepbound has to stop, since it's approved “to reduce excess body weight and maintain weight reduction long term” [1]. Whether you stay on it long term is a decision for you and your prescriber.
SURMOUNT-4 shows what's at stake. Of 783 participants entering a 36-week open-label tirzepatide lead-in, 670 were then randomized to continue tirzepatide or switch to placebo for 52 weeks. From week 36 to week 88, people who stayed on tirzepatide lost another 5.5% of their weight. People switched to placebo regained 14.0% [4]. Those percentages use week 36 weight as their baseline. At week 88, average weight remained 9.9% below the original baseline after switching to placebo and 25.3% below with continued treatment. The study does not establish an individual outcome or that stopping is universally risk-free; discuss ongoing care with the prescriber.
Before surgery and with other medicines
Tell every clinician you take Zepbound before surgery or sedation, because the label warns about rare cases of food getting into the lungs during anesthesia with this drug class. The label says available data do not establish whether changing fasting instructions or temporarily discontinuing treatment reduces retained gastric contents and aspiration risk [1]. Your surgical team decides.
- Insulin or sulfonylureas: the label says combining them with Zepbound may raise the risk of low blood sugar, and their dose may need lowering [1].
- Other pills: Zepbound slows stomach emptying, so the label urges caution with oral medicines, especially ones with narrow safety margins such as warfarin.
- Birth control pills: the label advises switching to a non-oral method, or adding a barrier method, “for 4 weeks after initiation with ZEPBOUND and for 4 weeks after each dose escalation” [1].
- Other tirzepatide or GLP-1 drugs: the label says taking Zepbound with them “is not recommended.”
Mounjaro’s adult and pediatric maximum doses differ
Mounjaro contains tirzepatide and has type 2 diabetes and certain adult cardiovascular indications, and its label also starts at 2.5 mg once a week. Its maximum is 15 mg for adults and 10 mg for children 10 and older [2]. More on the molecule is in tirzepatide, and the pharmacy-made version is covered in compounded tirzepatide.