Tirzepatide 60 mg reconstitution calculator

Zepbound and Mounjaro both come as a 60 mg/2.4 mL multi-dose vial or KwikPen (25 mg/mL), holding four 15 mg doses (Zepbound label, Mounjaro label). 15 mg once weekly is the maximum dosage on both labels (for Mounjaro, in adults; 10 mg in children). It’s a ready-made liquid: if your vial or pen reads “60 mg/2.4 mL”, don’t add bacteriostatic water. The KwikPen instructions also say not to transfer the medicine from the pen into a syringe. A 60 mg vial of powder that needs water is compounded or unapproved, and compounded drugs aren’t FDA-approved (FDA).

A mixed 60 mg vial holds 0.3 mg per unit with 2 mL and 0.2 mg with 3 mL. That’s six times what a unit holds in a 10 mg vial mixed with 2 mL (0.05 mg), so reading one mark too high moves six times as much medicine. The labeled 60 mg/2.4 mL vial sits between the two mixes, at 0.25 mg per unit, so units from it don’t transfer either. The FDA has received adverse event reports that may be related to compounded tirzepatide used in doses beyond the FDA-approved label, and it encourages patients to ask their health care provider or compounder how to measure the intended dose (FDA). Check your units with the pharmacist before the first draw.

Vial size doesn’t change the clock. The labeled 60 mg multi-dose vial is thrown away after 4 weekly doses, 30 days after first use or 30 days in total at room temperature, even if medicine is left (Zepbound label). For compounded multi-dose GLP-1 vials, the FDA says to discard within 28 days of first use, even if the compounder says longer (FDA). A 60 mg vial holds six times what a 10 mg vial holds within that same window. Use the calculator above to see how many draws of your prescribed amount the vial holds, and ask your pharmacist what to do if that won’t be used up before the date.