Enter the vial, the water you added and your dose. The calculator gives the units to draw on a U-100 insulin syringe. Or enter the units you drew to see the dose they delivered.
Stack logs each dose, rotates injection sites and tracks what is left in the vial. Everything stays on your phone, with no account. Free to try.
Get Stack on Google Play Open Stack in your browserReconstitution is dissolving a freeze-dried (lyophilised) peptide in bacteriostatic water so it can be measured and injected. The calculation has three steps.
1 mg is 1000 mcg. A 5 mg vial holds 5000 mcg.
Every row is a 5 mg vial and a 250 mcg dose. Only the water changes.
| Water added | Concentration | Units to draw |
|---|---|---|
| 1 mL | 5000 mcg/mL | 5 units |
| 2 mL | 2500 mcg/mL | 10 units |
| 3 mL | 1667 mcg/mL | 15 units |
| 5 mL | 1000 mcg/mL | 25 units |
The dose is the same in every row. Only the volume you draw changes, and more water makes it a larger draw that is easier to read on the barrel.
| Units | Volume |
|---|---|
| 5 units | 0.05 mL |
| 10 units | 0.10 mL |
| 25 units | 0.25 mL |
| 50 units | 0.50 mL |
| 100 units | 1.00 mL |
Syringes hold 30 units (0.3 mL), 50 units (0.5 mL) or 100 units (1 mL). A draw larger than the barrel needs two draws or less water.
Divide the vial amount by the volume of bacteriostatic water added to get the concentration. Divide your dose by that concentration to get the volume to draw in millilitres. On a U-100 insulin syringe, multiply that volume by 100 to get units, because 100 units equals 1 mL.
A 5 mg vial in 2 mL of water gives 2500 mcg per mL. A 250 mcg dose is 0.1 mL, which is 10 units on a U-100 insulin syringe.
No. The vial holds the same total amount of peptide however much water you add. More water spreads it across a larger volume, so you draw more units to get the same dose. Some people use more water when the dose is very small, because a larger draw is easier to measure.
On a standard U-100 insulin syringe, 100 units is 1 mL. So 50 units is 0.5 mL and 10 units is 0.1 mL. The unit markings measure volume, not the amount of peptide.
1 mg is 1000 mcg. Multiply milligrams by 1000 to get micrograms, or divide micrograms by 1000 to get milligrams. A 5 mg vial holds 5000 mcg.
Bacteriostatic water contains a small amount of benzyl alcohol, which lets a vial be entered more than once over a period of time. Plain sterile water has no preservative, so it is generally used for single-use situations. The calculation is the same either way, because the type of water does not change the math.
Either split it across two draws, or reconstitute with less water next time so the same dose sits in a smaller volume. The calculator flags this when it happens.
This calculator does arithmetic on the numbers you enter. It does not know what is appropriate for you, and it is not medical advice, a dosing recommendation or a substitute for a qualified healthcare professional. Many peptides are not approved for human use, and legal status varies by country. Check your own numbers independently before drawing anything.