Mounjaro dosage: how the step-up schedule works, from 2.5 mg to 15 mg

What this guide covers

Mounjaro (tirzepatide) is a once-weekly injection with six dose strengths that climb slowly on purpose. Here is what the FDA label says: why you start at 2.5 mg, how the increases are spaced, what the maintenance doses are, and why the slow climb matters for how well you tolerate it. This is patient education, not a substitute for the prescriber who knows your case. Generic names sit next to brand names throughout: semaglutide (Ozempic, Wegovy), tirzepatide (Mounjaro, Zepbound).

Key points

• The short answer: a slow ladder from 2.5 mg to 15 mg. Mounjaro is the brand name for tirzepatide, a once-weekly injection given under the skin. It comes in six strengths that climb in even steps: 2.5 mg, 5 mg, 7.5 mg, 10 mg, 12.5 mg, and 15 mg. The FDA label sets out a starting dose and a schedule for stepping up, and the whole point of that schedule is to give your body time to adjust. You begin low, hold there for a set stretch, and only then move up, with your prescriber deciding each step. Nobody starts at a high dose, and there is no single dose that is right for everyone. Where you settle depends on how you respond and how well you tolerate it, which is a conversation with your doctor rather than a number to chase on your own.
• Why you start at 2.5 mg, and why it is not your real dose. The 2.5 mg starting dose is described in the label as a starting dose that is not intended for treatment; it is there to let your gut get used to the drug before the strength that actually does the work. Tirzepatide slows how quickly the stomach empties and dampens appetite, and those same actions are what drive the early nausea and other digestive effects, so easing in at a low dose is how the schedule keeps the first weeks manageable. You stay at 2.5 mg for four weeks. Think of it as the on-ramp rather than the journey: it matters, but it is not where most people stay, and feeling little effect at this dose is expected rather than a sign the drug is not working.
• The step-up schedule, one increase at a time. After the four weeks at 2.5 mg, the label moves you to 5 mg, the first dose meant to treat. From there, if you and your prescriber decide more is needed, the dose can go up by 2.5 mg at a time, and each increase should come only after at least four weeks on the current dose. So the ladder runs 2.5, then 5, then 7.5, 10, 12.5, and 15 mg, with a four-week minimum on each rung before the next. Not everyone climbs the whole ladder; many people find a dose that works for them partway up and stay there. The four-week spacing is a floor, not a deadline, and a prescriber can hold you longer on any rung if a step up is proving rough.
• What counts as a maintenance dose. The label lists 5 mg, 10 mg, and 15 mg as the maintenance doses, with 7.5 mg and 12.5 mg as the intermediate steps you pass through on the way up. In plain terms, once you reach a dose that gives you the effect you and your doctor are looking for and that you tolerate, that becomes your maintenance dose, and you can stay there rather than automatically pushing to 15 mg. The maximum is 15 mg once weekly; there is no higher approved dose. Higher is not automatically better, and the right maintenance dose is the lowest one that does the job for you, which is why this is a decision made with your prescriber over time rather than a target set on day one.
• How and when to take it: once weekly, any day, with or without food. Mounjaro is injected under the skin once a week, on the same day each week, and it can be taken at any time of day with or without food. The usual injection sites are the abdomen, thigh, or upper arm, and rotating the spot each week is the standard advice. If you need to, you can change which day of the week you inject as long as it has been at least three days (72 hours) since your last dose. Each pen or vial is a single strength, so a dose change means a different pen rather than a different amount from the same one, which is worth knowing when you pick up a new prescription at a higher step.

Frequently asked questions