HGH (somatropin) dosage calculator
Growth hormone is the one compound here labelled in IU rather than mg. Enter the IU on your vial, the water you added and your IU dose to get the mark on the syringe.
25 printable pages: dosing cards for the twelve most-used compounds at three water volumes, titration planners, a vial log, and five pages on what to do when it has already gone wrong.
Dose to units at the usual vial and water
| Dose | U-100 units | Draw | Doses per vial | Vial lasts |
|---|---|---|---|---|
| 1 IU | 10 units | 0.1 mL | 10 | 10 days |
| 2 IU | 20 units | 0.2 mL | 5 | 5 days |
| 3 IU | 30 units | 0.3 mL | 3 | 3 days |
| 4 IU | 40 units | 0.4 mL | 2 | 2 days |
| 5 IU | 50 units | 0.5 mL | 2 | 2 days |
| 6 IU | 60 units | 0.6 mL | 1 | 1 day |
10 IU vial in 1 mL of bacteriostatic water (10 IU/mL), U-100 insulin syringe, once daily.
About HGH (somatropin)
Somatropin is recombinant human growth hormone, a 191 amino acid protein. It is a prescription medicine with licensed uses, and any use outside a prescription is unlicensed. Vials sold as research material are not the licensed product.
The unit confusion here is specific: the vial is labelled in international units (IU), not milligrams, and the syringe is labelled in insulin units. They are unrelated. 1 mg of somatropin is roughly 3 IU. A 10 IU vial reconstituted with 1 mL gives 10 IU per mL, so 2 IU is 0.2 mL, which is 20 units on a U-100 insulin syringe. That 20 has nothing to do with the IU figure; it is a volume.
Growth hormone is fragile once reconstituted. Swirl, never shake, and keep it refrigerated. Reported protocols commonly run 1 to 4 IU per day, often split, but that is a description of what people report and not a recommendation.
The same 10 IU vial at other water volumes
If the draw is awkward to read, change the water, not the dose. The dose stays the same; only the mark moves.
| Vial | BAC water | Concentration | Draw | U-100 units | Doses/vial |
|---|---|---|---|---|---|
| 10 IU | 1 mL | 10 IU/mL | 0.2 mL | 20 units | 5 |
| 10 IU | 2 mL | 5 IU/mL | 0.4 mL | 40 units | 5 |
| 10 IU | 3 mL | 3.33 IU/mL | 0.6 mL | 60 units | 5 |
| 12 IU | 1 mL | 12 IU/mL | 0.167 mL | 16.7 units | 6 |
| 12 IU | 2 mL | 6 IU/mL | 0.333 mL | 33.3 units | 6 |
| 12 IU | 3 mL | 4 IU/mL | 0.5 mL | 50 units | 6 |
All rows above assume a 2 IU dose and a standard U-100 insulin syringe, where 100 units = 1 mL.
How long it lasts in the body
The half-life of HGH (somatropin) is about 3.8 hours. That is the time for the amount in your blood to halve, so after one half-life you are at 50 percent of the peak, after two you are at 25 percent, and after four you are at roughly 6 percent. This is why it is dosed daily or more often: by the next morning almost none of the previous dose is left, and there is no build-up from day to day.
Common questions
- How many units is 2 IU of HGH (somatropin)?
- It depends entirely on how much water you added. In a 10 IU vial reconstituted with 1 mL, the concentration is 10 IU/mL, so 2 IU is 0.2 mL, which is 20 units on a U-100 insulin syringe. In the same vial with 0.5 mL of water it is 10 units, and with 1.5 mL it is 30 units.
- How much bacteriostatic water for a 10 IU HGH (somatropin) vial?
- 1 mL is the usual choice. It gives 10 IU/mL, which puts the commonly reported range of 0.5 IU to 6 IU between roughly 5 and 60 units. Aim for a draw between about 10 and 50 units, where the barrel is easiest to read, and add or remove water to get there.
- How many doses are in a 10 IU vial?
- Divide 10 by your dose. At 2 IU that is 5 doses, which at once daily is 5 days.
- How many units is 2 IU of HGH?
- It depends on the water. A 10 IU vial with 1 mL of water is 10 IU/mL, so 2 IU is 0.2 mL, which is 20 units on a U-100 insulin syringe. With 2 mL of water the same 2 IU is 40 units.
- How many mg is 10 IU of HGH?
- About 3.3 mg. The conversion for somatropin is roughly 3 IU per mg. You do not need it for the calculator, which works in IU throughout.
Buying HGH (somatropin)?
The where to buy page lists the vendors this site uses and what to check first. Peptide Bureau keeps the ranked scorecard.
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Dosage charts and schedules
- Peptide reconstitution chart Concentration for every vial and water combination
- Peptide dosing chart Printable unit tables for every compound
- Retatrutide titration schedule 2 to 12 mg in units, stage by stage
- Tirzepatide titration schedule 2.5 to 15 mg in units, stage by stage
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- KLOW dosage and frequency chart The 80 mg blend at 2, 3 and 4 mL, both phases
- GLOW dosage chart The 70 mg blend, units to each peptide
- Wolverine stack dosing chart BPC-157 + TB-500, blend and separate vials
- MOTS-c dosage chart 5 and 10 mg vials at three water volumes
- Tirzepatide reconstitution chart Every vial size, every water volume, the whole ladder
- Retatrutide dosing chart 1 to 12 mg across 10, 20 and 30 mg vials
- Printable dosing charts Four one-page charts to save, pin or print
Tools
- Peptide calculator The general tool, any compound
- Reconstitution calculator How much water to add, and why it matters
- mg to units calculator Both directions, any concentration
- Bacteriostatic water calculator Pick a volume that lands where you can read it
- How to read an insulin syringe U-100 vs U-40, and the 2.5x error
- The Protocol Pack Free 25-page printable reference
- Where to buy Vendor notes and what to check first
- 1 mg to units on an insulin syringe The conversion table for every common concentration