Reconstitution calculator

Tirzepatide reconstitution calculator

A 10 mg Tirzepatide vial with 2 ml of bacteriostatic water holds 5,000 mcg per ml - so 2,500 mcg, as pure arithmetic, is a 50-unit draw on a U-100 insulin syringe. Change any of those numbers and the answer moves; the calculator below does the moving for you, and further down is the thing the vendor calculators never mention: where Tirzepatide actually stands with regulators right now.

Tirzepatide reconstitution calculator

Math on the numbers you enter - nothing more. Peptlas sells nothing and suggests no amounts.

Enter your intended dose above and the draw appears here, with the math shown.

Results are arithmetic, not advice. Peptlas is a regulatory-status reference: it does not recommend amounts, schedules, or use of any compound. Read the full disclaimer.

What you are working with

Brand tirzepatide (Mounjaro, Zepbound) is sold in ready-to-use pens and vials. The reconstitution math below applies only to compounded or gray-market lyophilized vials, commonly labeled 5 mg, 10 mg, or 15 mg.

The reference table below shows the concentration each common vial-and-water combination produces. These are arithmetic facts about Tirzepatide vial sizes, not guidance about amounts - the same table exists for BPC-157 and TB-500 (Thymosin Beta-4), with different numbers.

Vial+ 1 ml water+ 2 ml water
5 mg5,000 mcg/ml2,500 mcg/ml
10 mg10,000 mcg/ml5,000 mcg/ml
15 mg15,000 mcg/ml7,500 mcg/ml

While you are here - where Tirzepatide stands

Restricted

Tirzepatide is an FDA-approved drug (Mounjaro, Zepbound), not a 503A bulk substance. After the FDA declared its shortage resolved in late 2024, the temporary enforcement discretion for compounding copies ended on February 18, 2025 for 503A pharmacies and March 19, 2025 for 503B outsourcing facilities; a federal court upheld the FDA's shortage determination in 2025. Broad compounding is no longer permitted - only narrow patient-specific 503A compounding for a documented clinical need remains - and the FDA has been issuing warning letters.

Restricted: Prescription-only, banned, controlled, or under active FDA enforcement. Verified Aug 11, 2026 (ET) · status held since Mar 19, 2025.

The full Tirzepatide status page, with every source

What changed last

  1. Public comment period closed on the FDA's proposal to permanently exclude tirzepatide from the 503B bulks list (extended from June 30). The proposal is not final - the FDA is now reviewing the record, with no announced decision date.

    Comment deadlineView on govinfo.gov

  2. FDA proposed to permanently exclude tirzepatide from the 503B bulks list, alongside semaglutide and liraglutide. This is a proposal in a comment period, not a final change.

    Review scheduledView on federalregister.gov

Tirzepatide math, asked and answered

How much bacteriostatic water do you add to a 10 mg Tirzepatide vial?
Any amount - water sets the concentration, not the contents. With 2 ml, a 10 mg vial gives 5,000 mcg/ml; with 1 ml it gives 10,000 mcg/ml. More water means the same dose is a larger, easier-to-read draw on the syringe. There is no single correct volume, which is why this page calculates instead of prescribing.
How many insulin-syringe units is 2,500 mcg of Tirzepatide?
It depends entirely on how the vial was reconstituted. As arithmetic: in a 10 mg vial with 2 ml of water (5,000 mcg/ml), 2,500 mcg is 50 units on a U-100 syringe. With 1 ml of water instead, the same 2,500 mcg is 25 units. The calculator above does this for your actual numbers.
Is Tirzepatide legal right now?
Restricted - Tirzepatide is an FDA-approved drug (Mounjaro, Zepbound), not a 503A bulk substance. After the FDA declared its shortage resolved in late 2024, the temporary enforcement discretion for compounding copies ended on February 18, 2025 for 503A pharmacies and March 19, 2025 for 503B outsourcing facilities; a federal court upheld the FDA's shortage determination in 2025. The full, source-linked answer is on the Tirzepatide status page, verified Aug 11, 2026 (ET).
What form does Tirzepatide come in?
Brand tirzepatide (Mounjaro, Zepbound) is sold in ready-to-use pens and vials. The reconstitution math below applies only to compounded or gray-market lyophilized vials, commonly labeled 5 mg, 10 mg, or 15 mg.

Other calculators and the atlas

Calculators:BPC-157TB-500 (Thymosin Beta-4)SemaglutideRetatrutideIpamorelinuniversal calculator

Status pages for every tracked compound:BPC-157CJC-1295Emideltide (DSIP)EpitalonGHK-CuIpamorelinKPVMelanotan IIMOTS-cNAD+RetatrutideSelankSemaglutideSemaxSermorelinTB-500 (Thymosin Beta-4)Thymosin Alpha-1the full atlas