Reconstitution calculator
prostamax — vial, water, dose. The barrel shows your draw.
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How much bacteriostatic water should I add?+
Most users add 1-3 mL. More water = lower concentration = easier to measure small doses. Use our Reverse Calculator to find the optimal volume.
What is the concentration after reconstitution?+
Concentration = vial size (mg) ÷ water added (mL). For a 5 mg vial with 2 mL water, the concentration is 2.5 mg/mL.
How do I read insulin syringe units?+
Each unit on a U-100 syringe = 0.01 mL. A 0.3 mL syringe has 30 units, a 0.5 mL syringe has 50, and a 1.0 mL syringe has 100.
Does the peptide type matter for reconstitution math?+
No — the reconstitution formula is universal. Concentration depends only on vial size and water volume, not the specific peptide.
How long does a reconstituted vial last?+
21-28 days when stored at 2-8°C (refrigerated) after reconstitution with bacteriostatic water.