Peptide reconstitution calculator

Three steps. Divide the peptide in the vial by the water you add to get the concentration in mg/mL. Divide your dose by that concentration to get the volume of one dose in mL. Multiply that volume by 100 to get the units to draw on a U-100 insulin syringe. A 5 mg vial with 2 mL of water is 2.5 mg/mL, so a 1 mg dose is 0.4 mL, which is 40 units.

There is no single correct amount, because the water does not change how much peptide you get. It only changes how big the draw is. More water gives a larger, easier to read draw. Less water gives a small, concentrated one where a misread costs more. Aim for a draw you can read comfortably on the barrel you own. If yours lands under about 5 units, use less water. If it runs past about 60 units, use a bigger barrel rather than more water.

The scale printed on it. U-100 means 100 units per mL, so one unit is 0.01 mL. U-40 means 40 units per mL, so one unit is 0.025 mL. The same 0.4 mL of liquid is 40 units on a U-100 barrel and 16 on a U-40. This calculator and the Milligram app both use U-100, which is what almost every insulin syringe sold for peptide use is. Check what is printed on your barrel before you draw, because the two are not interchangeable.

Four, and they are the same four the Milligram app uses: 0.3 mL, 0.5 mL, 1 mL and 3 mL. The first three are U-100 insulin syringes and differ in how fine their printed marks are. The 0.3 mL and 0.5 mL print every single unit. The 1 mL prints every 2 units with numerals every 25. The 3 mL reads in millilitres rather than units. The calculator rounds your draw to the nearest mark your barrel actually prints, and tells you what that rounded draw really delivers.

A unit is a mark on the syringe, not an amount of peptide. On a U-100 barrel, 100 units is 1 mL, so one unit is 0.01 mL of liquid. How much peptide sits in that unit depends entirely on your mix. At 2.5 mg/mL, one unit carries 25 mcg. Change the water and the same 40-unit draw delivers something different.

Same maths. This page runs the same solver as the app, including the barrel recommendation and the rounding to printed marks. The app adds what a web page cannot: it remembers every vial and mix, counts down the doses left in each one, models your blood levels between injections, and tells you when the next dose is due.