Zepbound Dosage Chart: Titration Schedule and Maximum Dose

Zepbound begins at 2.5 mg a week for 4 weeks, then climbs 2.5 mg at a time, at least 4 weeks apart, to 15 mg (Zepbound prescribing information, section 2). The doses you can stay on are 5, 10 and 15 mg, and 15 mg can begin in week 21 at the earliest.

Key facts

• The first dose is for starting only; the label says it "is not approved as a maintenance dosage" (Zepbound label, section 2.1).
• For obstructive sleep apnea, only the two highest maintenance doses are used (Zepbound label, section 2.2).
• Over 72 weeks, average weight fell 20.9% on the top dose and 15.0% on the lowest maintenance dose, against 3.1% on placebo (Zepbound label, section 14.1).
• Four weekly doses into a new strength, the level is about 98% of where it settles, worked out in the GLP‑1 Plotter from the label half-life.
• Shots can be up to 4 days (96 hours) late, and two doses need 3 days (72 hours) between them (Zepbound label, section 2.3).

Zepbound dose steps and the earliest week for each

Each Zepbound dose lasts at least 4 weeks, which fixes the earliest week for every step of the tirzepatide titration schedule (Zepbound label, section 2.1). Only the move from 2.5 mg to 5 mg happens after exactly 4 weeks; any later step can come later than the week shown.

Week 21 comes from five steps of 4 weeks each, 5 × 4 = 20 weeks on lower doses. Starting on Monday, October 5, 2026, the earliest dates would be 5 mg on November 2 and 7.5 mg on November 30. The 10 mg step could follow on December 28, then 12.5 mg on January 25, 2027 and 15 mg on February 22, 2027.

For your own dates, enter the dose you are on and the day of your first shot at it in the dose titration planner. Ozempic’s and Wegovy’s dose steps differ from Zepbound’s, with lower starting doses and different top doses.

Which dose to stay on

The maintenance doses for weight reduction are 5 mg, 10 mg and 15 mg once a week, and for obstructive sleep apnea 10 mg or 15 mg (Zepbound label, section 2.2). Which one you stay on depends on how well it works for you and how well you tolerate it (section 2.1). The 7.5 mg and 12.5 mg doses are steps between them. The first dose is not one you stay on: "The 2.5 mg dosage is for treatment initiation and is not approved as a maintenance dosage" (section 2.1).

In Study 1, 2,539 adults with obesity or overweight and without type 2 diabetes took a fixed Zepbound dose or placebo for 72 weeks (Zepbound label, section 14.1, Table 2). The placebo group lost 3.1% on average. The nausea column pools Studies 1 and 2, where 8% had nausea on placebo (section 6.1, Table 1).

In Study 1, the share who lost at least 15% of their weight was 48.0% on 5 mg, 66.6% on 10 mg and 70.6% on 15 mg, against 8.8% on placebo (Table 2).

When you can step up

Each step needs at least 4 weeks on the dose before it, and the label sets no latest date for it (Zepbound label, section 2.1). In the weight trials, the majority of nausea, vomiting and diarrhea after a Zepbound step-up happened during dose escalation and decreased over time (section 6.1). To keep each step on its dates, Pensday reminds you on your shot day.

Zepbound slows stomach emptying, which can make birth control pills less effective (Zepbound label, section 8.3). If you take them, switch to a non-oral method or add a barrier method for 4 weeks after starting and for 4 weeks after each dose increase.

If a shot slips, a late Zepbound shot can still go in within 4 days (96 hours), as long as the next one comes at least 3 days (72 hours) after it (section 2.3).

Why each step lasts at least 4 weeks

Tirzepatide levels reach steady state after 4 weeks of once-weekly shots, and the half-life is about 5 to 6 days in people with overweight or obesity (Zepbound label, section 12.3). Each shot goes in before the last one has cleared, so the level climbs for about 4 weeks after a new dose begins.

By the fourth dose on a new strength, tirzepatide sits at about 98% of its settled level, by the GLP‑1 Plotter's arithmetic from the label’s half-life. Exposure rises in proportion to the dose, so the same climb follows every step. The label’s reason for climbing slowly is to reduce the risk of stomach side effects (section 2.1).

Pens, vials and compounded tirzepatide

Every Zepbound format comes in the same six strengths and follows this ladder (Zepbound label, section 3). Single-dose pens and vials hold one 0.5 mL dose, while the KwikPen and the multi-dose vial hold four doses of 0.6 mL.

A compounded tirzepatide vial is dosed from the concentration on its label, and a vial labeled 5 mg/0.5 mL holds 10 mg/mL (5 ÷ 0.5). The tirzepatide dose calculator turns any dose into syringe units for that concentration.