Tirzepatide Reconstitution Calculator

A dual GIP and GLP-1 receptor agonist. FDA-approved for type 2 diabetes (Mounjaro) and chronic weight management (Zepbound).

Informational only. Not medical advice. Consult a licensed healthcare provider before starting, changing, or stopping any protocol.

Reconstitution calculator

Tirzepatide

Syringe type
Your dose
Draw 50 units
That's 0.5 mL of your reconstituted solution · Concentration 5,000 mcg/mL
This vial gives you 4 doses at 2,500 mcg
010203040506070809010050 units
Math is open source · Educational use only · Not medical advice

About Tirzepatide

FDA-approved prescription drug. Available via licensed prescriber.

Tirzepatide is a first-in-class dual agonist at the GIP (glucose-dependent insulinotropic polypeptide) and GLP-1 receptors. FDA-approved as Mounjaro (2022) for type 2 diabetes and Zepbound (2023) for chronic weight management. The SURPASS trials established efficacy in diabetes; the SURMOUNT trials established efficacy in obesity, with 15–20%+ average body weight reduction at maintenance dose.

Half-life is approximately 5 days (120 hours). Dosed once weekly subcutaneously. Titration starts at 2.5 mg/week and escalates every 4 weeks: 2.5 → 5 → 7.5 → 10 → 12.5 → 15 mg/week depending on indication and tolerability. Compounded tirzepatide has been available via 503A/503B pharmacies amid shortages; regulatory landscape is evolving.

Brand names: Mounjaro, Zepbound

Frequently asked questions

How does tirzepatide differ from semaglutide?
Semaglutide is a selective GLP-1 receptor agonist. Tirzepatide activates both GIP and GLP-1 receptors. In head-to-head trials (SURPASS-2), tirzepatide produced greater body weight and HbA1c reductions vs. semaglutide at comparable tolerability profiles.
What's a common vial + BAC water combination?
Compounded tirzepatide is commonly supplied as 10 mg vials reconstituted with 1 mL or 2 mL BAC water, yielding 10 mg/mL or 5 mg/mL respectively. Your calculator result depends on your specific vial.
What's the 5 mg "titration jump"?
Tirzepatide titration steps typically move in 2.5 mg increments: 2.5 → 5 → 7.5 → 10 → 12.5 → 15. Each step is typically held for 4 weeks before escalating.

Sources

  1. Jastreboff AM, et al. "Tirzepatide Once Weekly for the Treatment of Obesity." NEJM. 2022 (SURMOUNT-1). PMID: 35658024
  2. Frías JP, et al. "Tirzepatide versus Semaglutide Once Weekly in Patients with Type 2 Diabetes." NEJM. 2021 (SURPASS-2). PMID: 34370970
  3. Mounjaro FDA Prescribing Information. Eli Lilly. 2022.

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