Tirzepatide is the compound with the most dosage searches of any peptide this site covers, and it is also the one where a label answers most of them. Two approved products carry a full dosing schedule, and a large trial published the regimen behind it. What no source supplies is the number people actually search for: how many syringe units a given milligram amount is in a powder vial, which depends on a concentration the label never had to state. This page reports the label and trial figures with their dates, and then works the arithmetic for the 10, 15 and 30 mg vials the research market sells.
Tirzepatide is a dual GIP and GLP-1 receptor agonist, a 39-residue peptide sold as Zepbound (obesity and obstructive sleep apnoea) and Mounjaro (type 2 diabetes), both from Eli Lilly. Medibact's Tirzepatide guide covers what it is and what the evidence shows; this page stays with the figures. The dosage hub lists every compound's page.
What the sources state
| Source | Kind | Figure | Date read |
|---|---|---|---|
| Zepbound label, Eli Lilly (DailyMed, version published 2026-09-02) | Approved label | 2.5 mg once weekly for 4 weeks; increase in 2.5 mg increments after at least 4 weeks; maintenance 5, 10 or 15 mg once weekly; maximum 15 mg once weekly | 2026-09-18 |
| Mounjaro label, Eli Lilly (DailyMed, version published 2026-09-02) | Approved label | Same 2.5 mg start and 2.5 mg steps; maximum 15 mg once weekly in adults, 10 mg once weekly from age 10 | 2026-09-18 |
| SURMOUNT-1, NCT04184622 (2,539 participants; results posted 2023-04-24) | Trial protocol | 2.5 mg start, +2.5 mg every 4 weeks to 5, 10 or 15 mg, held to week 72 | 2026-09-18 |
| Jastreboff et al., NEJM 2022 (PMID 35658024) | Trial publication | Mean weight change at week 72: -15.0% (5 mg), -19.5% (10 mg), -20.9% (15 mg), -3.1% (placebo) | 2026-09-18 |
| Clinic, telehealth and calculator pages | Commonly cited | Compounded concentrations of 5, 10, 15, 17 and 20 mg/mL; the label's milligram steps converted to units at each | 2026-09-18 |
Two things are worth noticing in that table. The label and the trial agree with each other exactly, because the label was written from the trial. And none of the five rows contains a figure for a powder vial, because no approved tirzepatide product is one: a DailyMed search on 2026-09-18 returned eight tirzepatide records, all Zepbound or Mounjaro solutions from Eli Lilly or a repackager.
The label's own arithmetic
The approved products state their concentration, which makes them the one place where "units" has a label-backed answer. The single-dose pens and vials hold 2.5, 5, 7.5, 10, 12.5 or 15 mg in 0.5 mL each. A 2.5 mg vial is therefore 5 mg/mL, a 5 mg vial is 10 mg/mL, and a 15 mg vial is 30 mg/mL; in every case the whole 0.5 mL is the dose, and 0.5 mL is 50 units on a U-100 syringe.
The multi-dose KwikPens and vials, listed on both labels as 10 mg to 60 mg per 2.4 mL, are built to deliver four 0.6 mL doses, so 0.6 mL, or 60 units, is one dose at whatever strength the pen carries. Those are the only unit figures on this page that come from a label rather than from arithmetic.
Units per dose at each research-vial size
Research-market tirzepatide is supplied in 10 mg, 15 mg and 30 mg vials. The table takes each vial at 1, 2 and 3 mL of water, states the concentration that results, and converts each label step into U-100 syringe units (100 units = 1 mL). Any cell over 100 units does not fit one syringe at that concentration.
| Vial | Water added | Concentration | 2.5 mg | 5 mg | 7.5 mg | 10 mg | 12.5 mg | 15 mg |
|---|---|---|---|---|---|---|---|---|
| 10 mg | 1 mL | 10 mg/mL | 25 | 50 | 75 | 100 | 125 (>1 syringe) | 150 (>1 syringe) |
| 10 mg | 2 mL | 5 mg/mL | 50 | 100 | 150 (>1 syringe) | 200 (>1 syringe) | 250 (>1 syringe) | 300 (>1 syringe) |
| 10 mg | 3 mL | 3.33 mg/mL | 75 | 150 (>1 syringe) | 225 (>1 syringe) | 300 (>1 syringe) | 375 (>1 syringe) | 450 (>1 syringe) |
| 15 mg | 1 mL | 15 mg/mL | 16.7 | 33.3 | 50 | 66.7 | 83.3 | 100 |
| 15 mg | 2 mL | 7.5 mg/mL | 33.3 | 66.7 | 100 | 133.3 (>1 syringe) | 166.7 (>1 syringe) | 200 (>1 syringe) |
| 15 mg | 3 mL | 5 mg/mL | 50 | 100 | 150 (>1 syringe) | 200 (>1 syringe) | 250 (>1 syringe) | 300 (>1 syringe) |
| 30 mg | 1 mL | 30 mg/mL | 8.3 | 16.7 | 25 | 33.3 | 41.7 | 50 |
| 30 mg | 2 mL | 15 mg/mL | 16.7 | 33.3 | 50 | 66.7 | 83.3 | 100 |
| 30 mg | 3 mL | 10 mg/mL | 25 | 50 | 75 | 100 | 125 (>1 syringe) | 150 (>1 syringe) |
The formula behind every cell is units = milligrams ÷ (milligrams per millilitre) × 100. Reading the table down a column shows why unit figures travel so badly between pages: 5 mg is 50 units in one row and 16.7 in another, and both are correct for their own vial. The tirzepatide calculator works the same arithmetic for any vial, water volume and amount entered, and the reconstitution chart lists the concentrations for every vial size on the site. The tirzepatide reconstitution page covers the water volumes per vial size in full.
Why the same milligram figure is quoted as 12.5 units on one page and 50 on another
Compounded tirzepatide is dispensed as a solution at a concentration the pharmacy chooses. Clinic, telehealth and calculator pages read on 2026-09-18 quoted 5, 10, 15, 17 and 20 mg/mL, and some published charts at more than one strength. At 20 mg/mL, 2.5 mg is 12.5 units; at 5 mg/mL it is 50 units. A chart that names its concentration is usable only for vials at that concentration; a chart that does not is not usable at all. This is a property of the arithmetic, not a comment on any page.
What the figures omit
The label states a weekly interval, a 4-week hold at each step and an approved indication, and every figure on it belongs to a solution whose concentration Lilly controls. The trial states an escalation and a 72-week duration in a population selected by BMI and comorbidity. A research vial supplies none of that: no interval, no hold, no population and no concentration until water is added. The arithmetic on this page transfers the milligram figures into units; it does not transfer the conditions under which they were measured.
Two further omissions are worth stating. Neither label describes reconstituting a powder, because neither product is one. And no label, trial or registry record read for this page reports a dose above 15 mg once weekly for the approved product.
Related pages
The two other incretin compounds on this site have their own pages: retatrutide dosage reports the phase 2 and TRIUMPH doses for a compound with no label, and semaglutide dosage reports the Wegovy and Ozempic schedules alongside the compounded-vial arithmetic. The store's comparison of tirzepatide and retatrutide covers the two molecules side by side. The general mixing procedure is documented on medibact.com's how to reconstitute peptides page; this site carries the per-compound arithmetic only.
The insulin syringe units how-to explains the U-100 and U-40 scales and how a milligram figure becomes a syringe reading.
What this page does not do
This page reports what the two labels, one trial and the public web state about tirzepatide, each with its source and the date it was read, and converts those figures into syringe units at the concentrations a research vial can produce. It does not recommend an amount, a concentration, an interval or a schedule, and none of the tables is a plan. Where a figure has conditions attached, the conditions belong to the source, not to the vial.
Sources and dates
Opened 2026-09-18: the Zepbound label on DailyMed (set id 487cd7e7-434c-4925-99fa-aa80b1cc776b, version published 2026-09-02) and the Mounjaro label on DailyMed (set id d2d7da5d-ad07-4228-955f-cf7e355c8cc0, version published 2026-09-02), both also read through the openFDA label endpoint; the DailyMed SPL search for tirzepatide (eight records, all Zepbound or Mounjaro); NCT04184622 on ClinicalTrials.gov (SURMOUNT-1, results posted 2023-04-24); PMID 35658024 (Jastreboff et al., NEJM 2022); and a read of clinic, telehealth and calculator pages for the compounded concentrations in circulation. Corrections go to the contact page.