HGH (Somatropin) Calculator
Also known as: Somatropin, Genotropin, Humatrope, Norditropin, Saizen, Omnitrope
What is HGH (Somatropin)?
Somatropin is recombinant human growth hormone — a 191-amino-acid polypeptide structurally identical to endogenous pituitary HGH. It is FDA-approved for several conditions, including pediatric growth hormone deficiency, adult growth hormone deficiency, Turner syndrome, idiopathic short stature, AIDS-associated wasting, and short bowel syndrome, and is sold under brand names including Genotropin, Humatrope, Norditropin, Saizen, and Omnitrope. Somatropin is conventionally measured in International Units (IU) at the long-standing clinical convention of approximately 3 IU per milligram. Vials are typically labelled in IU — a 10 IU vial corresponds to about 3.33 mg of somatropin. Reconstituted with bacteriostatic water, it is administered as a daily subcutaneous injection. The compound has a short circulating half-life of two to three hours, with most physiological effects mediated downstream through insulin-like growth factor 1.
| 6 IU | lyophilized powder |
| 10 IU | lyophilized powder |
| 12 IU | lyophilized powder |
| 16 IU | lyophilized powder |
| 24 IU | lyophilized powder |
| 36 IU | lyophilized powder |
| 1 IU | ≈ 10 U-100 units (at 10IU / 1mL) |
| 2 IU | ≈ 20 U-100 units (at 10IU / 1mL) |
| 3 IU | ≈ 30 U-100 units (at 10IU / 1mL) |
| 4 IU | ≈ 40 U-100 units (at 10IU / 1mL) |
How it's typically prepared
Inject bacteriostatic water slowly along the inner wall of the vial and swirl gently — do not shake, since somatropin is a fragile glycoprotein. Refrigerate the reconstituted solution at 2–8 °C; in-use stability is brand-specific and typically falls in the 14- to 28-day range. A U-100 insulin syringe is appropriate because IU values map cleanly to its 100-unit-per-mL scale.
Frequently asked questions
- How many IU is 1 mg of HGH?
- By the standard clinical conversion, 1 mg of somatropin is approximately 3 IU. A 10 IU vial therefore contains about 3.33 mg of somatropin; a 6 IU vial contains roughly 2 mg.
- How much bacteriostatic water do I add to an HGH vial?
- Manufacturer guidance varies by brand and vial size. Typical reconstitution volumes are 1 mL for a 6–12 IU vial or 1.5–2 mL for larger vials. Always follow the volume specified in your specific vial's prescribing information.
- How many U-100 units is 1 IU of HGH?
- It depends on the reconstitution. A 10 IU vial in 1 mL of BAC water yields a 10 IU/mL concentration, so 1 IU equals 0.1 mL or 10 units on a U-100 insulin syringe. Using 2 mL of BAC water halves the concentration to 5 units per IU.
- What is the difference between IU and mg dosing?
- International Units measure biological activity, while milligrams measure mass. For somatropin specifically, 1 mg is approximately 3 IU. Prescribing labels and reconstitution guides typically use IU; some clinical literature and compounded products use mg.
- How long does a reconstituted HGH vial last?
- In-use stability for refrigerated reconstituted somatropin is brand-dependent. Genotropin, Humatrope, and Norditropin each publish specific in-use periods on their FDA prescribing labels — typically 14 to 28 days at 2–8 °C.
Other GHS peptides
PeptideDose is an educational reference. It is not medical advice and does not replace consultation with a licensed healthcare provider. Doses shown in presets are derived from published protocols and product labels — they are not personal recommendations.