HGH reconstitution calculator
- Concentration
- 5 mg/mL
- Doses per vial
- 25
- Weeks (1 dose/wk)
- 25
4 units (0.04 mL) on a 1 mL U-100 syringe: 0.2 mg from a 5 mg vial + 1 mL water (HGH).
Dosing table for a 5 mg vial
Syringe units (U-100) for each dose, by how much bacteriostatic water you add.
| Dose | 1 mL water | 3 mL water |
|---|---|---|
| 0.15 mg | 3 | 9 |
| 0.2 mg | 4 | 12 |
| 0.3 mg | 6 | 18 |
How the math works
Concentration is the vial's milligrams divided by the water you add. Volume to draw is your dose divided by that concentration. On a U-100 syringe, 1 mL is 100 units, so units = mL × 100.
0.2 mg ÷ 5 mg/mL = 0.04 mL
0.04 mL × 100 = 4 units
How many units is 0.2 mg of HGH?
With a 5 mg vial and 1 mL of bacteriostatic water, 0.2 mg is 4 units (0.04 mL) on a U-100 syringe. With 3 mL of water it is 12 units. The answer always depends on how much water was added.
How much bacteriostatic water for a 5 mg HGH vial?
The water only sets the concentration; the amount of HGH in the vial stays the same. 1 mL makes 5 mg/mL, so 0.2 mg is 4 units. 3 mL makes 1.667 mg/mL, so the same 0.2 mg is 12 units. More water makes small doses easier to measure but needs more volume per injection.
How many 0.2 mg doses are in a 5 mg vial?
5 ÷ 0.2 = 25, so 25 full doses of 0.2 mg. Any liquid lost in the needle and vial is not counted.
What is the difference between IU and units on the syringe?
An IU measures the amount of somatropin (3 IU per mg on the Humatrope label), while a unit on a U-100 syringe is 0.01 mL, so the same IU dose reads differently at each concentration.
Calculated from IU per mg 3; mL per syringe unit 0.01; example concentration mg per mL 2.08. Formula: 1 IU = 1/3 mg = 0.333 / 2.08 mL = 0.16 mL = 16 syringe units at 2.08 mg/mL
Vial sizes, water volumes and preset doses are amounts quoted in HGH labels, used here for the arithmetic only. They are not dosing guidance.
Humatrope strengths and mixing volumes on the label
The Humatrope label gives each cartridge strength in both units: 6 mg (18 IU), 12 mg (36 IU) or 24 mg (72 IU) of somatropin.[4]
Its reconstitution table gives the resulting concentrations: 2.08 mg/mL for the 6 mg cartridge, 4.17 mg/mL for 12 mg and 8.33 mg/mL for 24 mg.[4]
For adults with GH deficiency the label lists a non-weight-based starting amount of approximately 0.2 mg/day, range 0.15 to 0.3 mg/day; this is label text for a diagnosed condition, not advice.[4]
Genotropin and Norditropin are labelled in mg
The Genotropin 5 mg cartridge reconstitutes to 5 mg/mL with a deliverable volume of 1 mL, and the label expresses strength in mg.[3]
The Genotropin 12 mg cartridge reconstitutes to 12 mg/mL with a deliverable volume of 1 mL.[3]
Norditropin pens are labelled 5 mg/1.5 mL, 10 mg/1.5 mL, 15 mg/1.5 mL and 30 mg/3 mL, in mg only; no IU strength is quoted here.[5]
One worked example on a label strength
A Humatrope 6 mg (18 IU) cartridge is 3 IU per mg, and at its labelled 2.08 mg/mL it holds 6.24 IU/mL.
Calculated from cartridge mg 6; cartridge IU 18; label concentration mg per mL 2.08. Formula: IU per mg = 18 / 6 = 3; IU/mL = 2.08 x 3 = 6.24
Drawing the label's 0.2 mg amount from that 2.08 mg/mL solution takes 0.096 mL, which reads 9.6 units on a U-100 syringe and equals 0.6 IU.
Calculated from amount mg 0.2; concentration mg per mL 2.08; IU per mg 3; units per mL 100. Formula: mL = 0.2 / 2.08 = 0.0962; syringe units = mL x 100 = 9.62; IU = 0.2 x 3 = 0.6
The same 0.2 mg amount from the 12 mg cartridge at 4.17 mg/mL takes 0.048 mL or 4.8 units, which is under 5 units and hard to measure accurately.
Calculated from amount mg 0.2; concentration mg per mL 4.17; units per mL 100. Formula: mL = 0.2 / 4.17 = 0.048; units = 4.8
IU and syringe units are different things
A U-100 syringe counts 100 units per mL, a volume measure. The insulin label is cited only for that unit definition, not for any growth hormone fact.[2]
Sources
- 1Metric (SI) Prefixes (NIST Reference on Constants, Units, and Uncertainty)National Institute of Standards and Technology (NIST) · 2025physics.nist.govAccessed 2 Oct 2026
- 2BASAGLAR (insulin glargine) injection, prescribing information (DailyMed)U.S. Food and Drug Administration / DailyMed (Eli Lilly and Company label) · 2026dailymed.nlm.nih.govAccessed 2 Oct 2026
- 3GENOTROPIN (somatropin) prescribing information (DailyMed)U.S. Food and Drug Administration / DailyMed (Pfizer label) · 2026dailymed.nlm.nih.govAccessed 2 Oct 2026
- 4HUMATROPE (somatropin) prescribing information (DailyMed)U.S. Food and Drug Administration / DailyMed (Eli Lilly and Company label) · 2026dailymed.nlm.nih.govAccessed 2 Oct 2026
- 5NORDITROPIN (somatropin) prescribing information (DailyMed)U.S. Food and Drug Administration / DailyMed (Novo Nordisk label) · 2026dailymed.nlm.nih.govAccessed 2 Oct 2026
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