Norditropin HGH Dosage Calculator
A reconstitution and dose calculator for Norditropin (somatropin), pre-set with the FlexPro 10 mg / 1.5 mL pen reference (≈ 30 IU at 20 IU/mL). Switch the inputs to match any FlexPro presentation — 5 mg, 10 mg, 15 mg, or 30 mg — to see the IU-per-millilitre concentration and the U-100 insulin-syringe equivalent for any target dose.
What is Norditropin?
Norditropin is Novo Nordisk's recombinant human growth hormone — somatropin — 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, and Noonan syndrome. The product is delivered via the FlexPro multi-dose pre-filled pen, which integrates a dial-a-dose mechanism designed for fixed-dose stepping.
Like all somatropin products, Norditropin is dosed by biological activity in International Units rather than by mass in milligrams. Pen labelling uses milligrams, but the underlying activity follows the long-standing 1 mg ≈ 3 IU clinical convention. A 10 mg FlexPro therefore contains about 30 IU of activity at a concentration of roughly 20 IU per millilitre — values reflected in the calculator above. Outside the growth-hormone family, HCG is the other reference peptide commonly labelled in IU for the same activity-based reason.
FlexPro pens are factory-reconstituted with a Novo Nordisk diluent and do not require adding bacteriostatic water. Storage guidance from the prescribing information is refrigeration at 2–8 °C with an in-use stability window of 28 days from first use for most presentations. Exact storage and stability details, plus dose-step compatibility with NovoFine needles, are documented in the FDA Norditropin label.
Norditropin FlexPro pen reference
Each row shows the pen presentation, its approximate IU equivalent at the standard 1 mg ≈ 3 IU conversion, the resulting concentration, and the U-100 syringe units that correspond to one IU at that concentration.
| Pen | IU equivalent | Concentration | Per 1 IU |
|---|---|---|---|
| 5 mg / 1.5 mL | ≈ 15 IU | 10 IU / mL | 10 units |
| 10 mg / 1.5 mL | ≈ 30 IU | 20 IU / mL | 5 units |
| 15 mg / 1.5 mL | ≈ 45 IU | 30 IU / mL | ≈ 3.3 units |
| 30 mg / 3 mL | ≈ 90 IU | 30 IU / mL | ≈ 3.3 units |
Source: Norditropin (somatropin) Prescribing Information — Novo Nordisk / FDA
Frequently asked questions
- How does this Norditropin dosage calculator work?
- Norditropin FlexPro pens arrive pre-filled and pre-reconstituted, but the underlying reconstitution math is identical to a vial: vial mass ÷ diluent volume = concentration. Enter the pen size in IU and the cartridge volume to see the IU/mL concentration and the U-100 syringe equivalent for any target dose.
- What are the Norditropin FlexPro pen sizes?
- Norditropin FlexPro is sold in four pre-filled multi-dose pens: 5 mg/1.5 mL, 10 mg/1.5 mL, 15 mg/1.5 mL, and 30 mg/3 mL. Using the standard 1 mg ≈ 3 IU conversion, those correspond to roughly 15 IU, 30 IU, 45 IU, and 90 IU respectively.
- How many IU is 1 mg of Norditropin?
- By the standard clinical convention, 1 mg of somatropin — the active ingredient in Norditropin — is approximately 3 IU. The 5 mg FlexPro therefore contains about 15 IU; the 10 mg FlexPro about 30 IU.
- How long does a Norditropin pen last after first use?
- Per the Novo Nordisk prescribing information, an opened Norditropin FlexPro pen is stable in refrigerated storage for up to 28 days from first use. Exact in-use stability is documented in the FDA prescribing label.
- Can I draw Norditropin into a separate insulin syringe?
- FlexPro is engineered for use with the integrated dial-a-dose mechanism and NovoFine needles. Drawing from the cartridge with a separate syringe is not the labelled administration route. The calculator's U-100 syringe figures are provided as an educational equivalence, not as administration guidance.
- Is Norditropin the same as Genotropin or Humatrope?
- All three are recombinant human growth hormone (somatropin) and share an identical 191-amino-acid sequence. They differ in delivery system, in-use stability, and excipients. Brand-specific reconstitution and storage details live on each manufacturer's prescribing information.
Keep reading
- HGH (Somatropin) full reference page — sources, FDA labels, side-effect profile.
- Growth hormone dose calculator — generic somatropin vial sizes, 4 IU – 36 IU.
- Insulin-syringe units explained — U-100 vs U-40 mechanics.
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.