PeptulatorReconstitution and dosing maths

IGF-1 LR3 dosage calculator

IGF-1 LR3 comes in very small vials and is dosed in tens of micrograms. The arithmetic is the same, but the numbers are small enough that the water volume decides whether you can read the draw at all.

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Dose to units at the usual vial and water

DoseU-100 unitsDrawDoses per vialVial lasts
10 mcg2 units0.02 mL100100 days
20 mcg4 units0.04 mL5050 days
30 mcg6 units0.06 mL3333 days
40 mcg8 units0.08 mL2525 days
50 mcg10 units0.1 mL2020 days
100 mcg20 units0.2 mL1010 days

1 mg vial in 2 mL of bacteriostatic water (0.5 mg/mL), U-100 insulin syringe, once daily.

About IGF-1 LR3

IGF-1 LR3 is a modified insulin-like growth factor 1 with an extended half-life. It is not an approved medicine and is sold for research use. It lowers blood sugar, and reports of hypoglycaemia at higher doses are common, which is one reason people who use it keep doses low.

A 1 mg vial holds 1,000 mcg. Reconstituted with 2 mL that is 500 mcg/mL, so 20 mcg is 0.04 mL, or 4 units. Some vials are only 100 mcg, in which case the whole vial is a few doses and 1 mL of water gives 100 mcg/mL. Check the label; a ten-fold error here is easy to make.

The same 1 mg 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.

VialBAC waterConcentrationDrawU-100 unitsDoses/vial
1 mg1 mL1 mg/mL0.02 mL2 units50
1 mg2 mL0.5 mg/mL0.04 mL4 units50
1 mg3 mL0.33 mg/mL0.06 mL6 units50
0.1 mg1 mL0.1 mg/mL0.2 mL20 units5
0.1 mg2 mL0.05 mg/mL0.4 mL40 units5
0.1 mg3 mL0.03 mg/mL0.6 mL60 units5

All rows above assume a 20 mcg dose and a standard U-100 insulin syringe, where 100 units = 1 mL.

How long it lasts in the body

The half-life of IGF-1 LR3 is about 20 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.

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Common questions

How many units is 20 mcg of IGF-1 LR3?
It depends entirely on how much water you added. In a 1 mg vial reconstituted with 2 mL, the concentration is 0.5 mg/mL, so 20 mcg is 0.04 mL, which is 4 units on a U-100 insulin syringe. In the same vial with 1 mL of water it is 2 units, and with 3 mL it is 6 units.
How much bacteriostatic water for a 1 mg IGF-1 LR3 vial?
2 mL is the usual choice. It gives 0.5 mg/mL, which puts the commonly reported range of 10 mcg to 100 mcg between roughly 2 and 20 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 1 mg vial?
Divide 1 by your dose. At 20 mcg that is 50 doses, which at once daily is 50 days.
How many units is 20 mcg of IGF-1 LR3?
In a 1 mg vial with 2 mL of water, 4 units on a U-100 syringe. In a 100 mcg vial with 1 mL of water, 20 units.
IndependentThis site does not sell peptides and is not owned by a vendor.
The maths is openThe formula is on every page and in the methodology. The code is one file with an automated test suite, run before each deploy.
How it earnsAffiliate links on one marked page, never inside the calculator.
ReviewedDose ranges and half-lives checked 3 September 2026.

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Tools

Before you use these numbers This is a unit-conversion tool. It turns a vial strength and a water volume into a concentration, a draw volume and a syringe mark. It does not tell you what to take, whether to take it, or whether a compound is safe for you. Most compounds listed are sold for laboratory research and are not approved for human use. Nothing here is medical advice. Dosing decisions belong with a licensed clinician who knows your history. Always check the strength printed on your own vial rather than trusting a preset.