IGF-1 LR3 reconstitution calculator.
A 1 mg vial of IGF-1 LR3 dissolved in 2 mL of bacteriostatic water is 500 mcg per mL, which is 5 mcg per unit on a U-100 insulin syringe.
IGF-1 LR3 is sold as a 1 mg vial, the smallest in the calculator's library, with amounts discussed in tens of micrograms rather than hundreds. That puts draws at the very bottom of a U-100 syringe, and it is dissolved in dilute acid rather than bacteriostatic water alone, so both the volume and what that volume is made of matter.
Reference range often cited for IGF-1 LR3: 20–60 mcg, shown for orientation only, not a recommendation. Enter your own target below. Read the evidence →
⚠ Very dilute solution: readings span many units, which can be hard to align precisely.
Each unit on a 100u · 1.0 mL syringe ≈ 5 mcg of this solution.
Show the math
More water → lower concentration → more units for the same amount.
How much bacteriostatic water for a IGF-1 LR3 vial?
There is no single correct volume. More water gives a weaker solution, so each unit on the syringe holds less IGF-1 LR3 and a given amount takes more units to measure, which is easier to read on the syringe scale. Less water does the opposite. These tables show the concentration for each common vial size across the usual volumes. They are arithmetic, not a recommendation of how much to take.
| BAC water | Concentration | Per 1 unit | Per 10 units |
|---|---|---|---|
| 1 mL | 1,000 mcg/mL | 10 mcg | 100 mcg |
| 1.5 mL | 667 mcg/mL | 6.7 mcg | 67 mcg |
| 2 mL | 500 mcg/mL | 5 mcg | 50 mcg |
| 2.5 mL | 400 mcg/mL | 4 mcg | 40 mcg |
| 3 mL | 333 mcg/mL | 3.3 mcg | 33 mcg |
How many units of IGF-1 LR3 is a given amount?
Divide the amount in micrograms by the micrograms per unit for your mix. With a solution of 2,500 mcg per mL, one unit on a U-100 syringe holds 25 mcg, so any amount in mcg divided by 25 gives the units. The calculator above does this for you from your own vial and water, and the tables give the per-unit figure for each common mix.
Why does IGF-1 LR3 need its own calculation?
- 1 mg in 1 mL is 1,000 mcg/mL, which is 10 mcg per unit, so 20 mcg is 2 units, the threshold below which the calculator warns about measurement error. In 2 mL the same 20 mcg is 4 units.
- It tends to aggregate at neutral pH, so the documented method dissolves it in a small volume of dilute acetic acid first and then makes it up with bacteriostatic water. Concentration is set by the total volume, acid included.
- IGF-1 LR3 is not mecasermin (Increlex), the only approved IGF-1 drug. That is native IGF-1 supplied as a ready-made solution, and its labeled concentration says nothing about an LR3 vial.
How is IGF-1 LR3 administered, and what does the math look like?
How IGF-1 LR3 is actually administered, with the concentration arithmetic written out. Amounts in these tables are illustrative examples of the math, never a recommendation.
IGF-1 LR3: research formats
Choose the format you are researching to see route-specific notes.
Requires acetic acid reconstitution; basic residues aggregate at neutral pH.
IGF-1 LR3 is a modified IGF-1 analog with extended half-life (~20–30 h vs 5–10 min for native IGF-1). It is sold as a 1 mg vial and requires 0.6% acetic acid for initial reconstitution because its basic residue composition causes aggregation at neutral pH. After dissolving, dilute with BAC water to the target volume.
At 1,000 mcg/mL and very small target volumes, measuring error is significant. A TB syringe (0.01 mL graduations) is more accurate than a U-100 at sub-10-unit draws.
Subcutaneous injection targets local muscle-group tissue; IM injection is used in some research designs. Route selection affects the delivery pattern.
IGF-1 LR3 reconstitution: common questions
How many units is 50 mcg of IGF-1 LR3?
On 1 mg in 1 mL (1,000 mcg/mL) it is 5 units. On 1 mg in 2 mL (500 mcg/mL) it is 10 units, the same amount at a reading that is easier to align.
Why does IGF-1 LR3 need acetic acid?
Its basic residues make it aggregate at neutral pH, so it is dissolved in dilute acetic acid first and then diluted with bacteriostatic water to the final volume. That final total volume is the figure to enter above.
Is IGF-1 LR3 the same as Increlex?
No. Increlex is mecasermin, recombinant native IGF-1, approved for severe primary IGF-1 deficiency. LR3 is a longer, modified analog engineered to escape the IGF binding proteins, and it is not approved for human use by any major regulator.
What the evidence on IGF-1 LR3 actually shows
Knowing the concentration is not the same as knowing whether to use it. These are the strongest studies behind the IGF-1 LR3 profile, labelled with the study type PubMed itself assigns.
- Journal article · 2008Enhancement of maternal lactation performance during prolonged lactation in the mouse by mouse GH and long-R3-IGF-I is linked to changes in mammary signaling and gene expressionThe Journal of endocrinology · PMID 18577570
- Journal article · 2003Site-specific fluorescent derivatization and liquid chromatographic-mass spectrometric characterization of long R(3) IGF-I for bioanalytical applicationsJournal of chromatography. B, Analytical technologies in the biomedical and life sciences · PMID 12880859
- Journal article · 1995Long R3 insulin-like growth factor-I (IGF-I) infusion stimulates organ growth but reduces plasma IGF-I, IGF-II and IGF binding protein concentrations in the guinea pigThe Journal of endocrinology · PMID 7561636
This page is arithmetic on numbers you enter. It does not recommend an amount of IGF-1 LR3, and nothing here is medical advice. For what the published evidence actually supports, read the IGF-1 LR3 profile, and for regulatory status see is IGF-1 LR3 legal. Reviewed June 1, 2026.
Different question? The general reconstitution calculator covers every compound on the site, the blend calculator handles multi-peptide stacks, and vial longevity turns a vial into weeks of supply.
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