How many units is a 50 mcg IGF-1 LR3 dose?

With a 1 mg IGF-1 LR3 vial reconstituted in 1 mL of bacteriostatic water (1000 mcg/mL), a 50 mcg dose works out to 50 divided by 10 mcg per unit, which is 5 units on a U-100 insulin syringe.

How much bacteriostatic water goes into an IGF-1 LR3 vial?

It depends on the concentration you want. A common reference point for a 1 mg vial is 1 mL, which gives 1000 mcg/mL and keeps typical research doses in a readable unit range. Use the calculator to test other volumes and find one that lands a dose on a round syringe mark.

Is IGF-1 LR3 FDA-approved?

No. IGF-1 LR3 is not FDA-approved for any use. It is sold as a research compound, not as a drug or supplement, and none of the figures in an IGF-1 LR3 dosage calculator describe an approved or recommended human dose.

Does an IGF-1 LR3 dosage calculator handle both mg and mcg?

Yes. Vial labels are almost always in milligrams while research doses are typically described in micrograms, often in the tens of micrograms for IGF-1 LR3. 1 mg equals 1000 mcg, and the calculator converts between the two automatically once a vial size, water volume, and target dose are entered.

IGF-1 LR3 Dosage Calculator: Reconstitution Guide

By PeptCalc Research — Medically reviewed by David Mansour, MD — Last reviewed August 13, 2026

IGF-1 LR3 vials are labeled in milligrams, while research doses are typically described in micrograms — often a much smaller number than the vial label suggests, which is exactly the conversion an IGF-1 LR3 dosage calculator is built to handle. This is a reference for that math: how vial size and bacteriostatic water volume set concentration, and how concentration turns a target dose into an exact draw on a U-100 insulin syringe. It is written for research purposes only and is not medical advice.

What the calculator does

An IGF-1 LR3 dosage calculator only needs three numbers to do its job: vial size, water volume, and target dose. The peptide calculator handles the conversion in two directions:

Forward mode — enter vial size, water volume, and target dose, and it returns the syringe units to draw.
Reverse mode — enter vial size, target dose, and a desired unit count, and it returns the water volume that produces it.

Both modes run on the same formula: concentration equals mass divided by water volume, and units equal that volume in mL multiplied by 100 on a U-100 syringe. That formula doesn't change because the vial holds IGF-1 LR3 instead of another peptide — only the vial's own mass and water volume matter, and IGF-1 LR3's small per-dose mass is exactly why getting the math right matters more here than with peptides dosed in whole milligrams.

IGF-1 LR3 at a glance

IGF-1 LR3, or Long R3 IGF-1, is a synthetic analog of human insulin-like growth factor 1 (IGF-1). It carries a 13-amino acid extension at the N-terminus along with a substitution of arginine for glutamic acid at the third position — the changes the "LR3" name refers to. Native IGF-1 binds tightly to IGF-binding proteins circulating in blood, which regulate how much of it is available to act on tissue at any given time. The LR3 modification reduces that binding, which is why researchers report it remains active longer than native IGF-1 in laboratory settings.

Most published work on IGF-1 LR3 comes from cell culture and animal-model research examining growth-related signaling pathways, rather than controlled human trials. IGF-1 LR3 is not FDA-approved for any use. It is sold as a lyophilized research compound, not as a drug or supplement, and nothing here describes a use recommendation. It describes reconstitution arithmetic, which is identical regardless of a compound's regulatory status or how established its research base is. For a peptide studied in a related growth-hormone-axis research context, see the CJC-1295 ipamorelin dosage chart.

Typical research concentration

IGF-1 LR3 most commonly reaches researchers as lyophilized powder in vials in the 0.1 mg to 2 mg range — smaller than the multi-milligram vials common to peptides like BPC-157 or TB-500, since IGF-1 LR3 research doses are typically measured in micrograms rather than whole milligrams. Reconstituted in 1 mL of bacteriostatic water, a reference point chosen because it keeps typical research doses on readable syringe marks:

Vial size	Water added	Concentration
0.1 mg	1 mL	0.1 mg/mL (100 mcg/mL)
1 mg	1 mL	1 mg/mL (1000 mcg/mL)
2 mg	1 mL	2 mg/mL (2000 mcg/mL)

These are reference points, not requirements — the free peptide calculator recalculates concentration for any vial size and water volume actually on hand.

The math

Step 1: Calculate concentration

Concentration = vial mass ÷ water volume

1 mg vial + 1 mL water = 1 ÷ 1 = 1 mg/mL (1000 mcg/mL)

Step 2: Convert concentration to mcg per unit

A U-100 insulin syringe divides 1 mL into 100 units, so:

mcg per unit = concentration (mcg/mL) ÷ 100

1000 mcg/mL ÷ 100 = 10 mcg per unit

Step 3: Convert the target dose to units

Units = target dose (mcg) ÷ mcg per unit

Worked example. A 1 mg IGF-1 LR3 vial reconstituted in 1 mL of bacteriostatic water is 1000 mcg/mL, which is 10 mcg per unit. A 50 mcg research reference dose from that vial is 50 ÷ 10 = 5 units. A 20 mcg dose from the same vial is 20 ÷ 10 = 2 units.

Compare that to the same 1 mg vial reconstituted in 2 mL of water instead: 1 ÷ 2 = 0.5 mg/mL, or 500 mcg/mL, which is 5 mcg per unit. That same 50 mcg dose is now 50 ÷ 5 = 10 units — a larger draw from a lower-concentration vial, even though the dose in mcg hasn't changed at all.

Choosing a water volume

Water volume is the lever that sets how large a given dose reads on the syringe. For a 1 mg vial and a 50 mcg dose:

Water added	Concentration	mcg per unit	Units for 50 mcg
1 mL	1000 mcg/mL	10 mcg/unit	5 units
2 mL	500 mcg/mL	5 mcg/unit	10 units
5 mL	200 mcg/mL	2 mcg/unit	25 units

None of these rows is more correct than another — 50 mcg is 50 mcg regardless of which row it comes from. A larger draw is generally easier to measure precisely on a U-100 barrel than a very small one, since a one-unit misread is a bigger proportional error at the low end — a real consideration with a compound dosed in the tens of micrograms. Reverse mode on the peptide dosage calculator finds the water volume that lands a specific dose on a round unit mark.

Reconstitution process

Gather the IGF-1 LR3 vial, bacteriostatic water, a U-100 insulin syringe, and alcohol swabs.
Swab both vial stoppers with alcohol.
Draw the water volume the chosen concentration calls for.
Inject it slowly down the inside wall of the vial, not directly onto the powder.
Swirl gently until fully dissolved — don't shake.
Confirm the resulting concentration matches what was entered into the calculator before drawing a dose.

For the general mixing walkthrough that applies to any peptide vial, see how to reconstitute peptides.

Storage

Reconstituted IGF-1 LR3 is generally kept refrigerated and protected from light. Unreconstituted lyophilized powder is far more stable than the mixed solution, which is why vials ship dry. Track the date each vial was reconstituted, particularly if more than one vial is in use at different concentrations.

Common mistakes

Confusing mg and mcg. IGF-1 LR3 vial labels are in milligrams; research doses are typically described in micrograms, and the gap between the two is especially easy to miss with a compound dosed in such small mass. 1 mg equals 1000 mcg, and misreading one for the other produces a 1000x error.
Treating research figures as established human dosing. IGF-1 LR3's human research base is thin, and most of what's published is preclinical. A number appearing in a research protocol is not the same as a validated clinical dose.
Reusing a unit count across a different water volume. As the table above shows, 50 mcg is 5 units at one concentration and 10 units at another. A unit count only means something relative to the specific concentration it was calculated from.
Using a syringe that isn't U-100. Every unit conversion here assumes 100 units equal 1 mL. A different syringe scale changes the math entirely.
Skipping a fresh concentration check after reconstitution. Confirm the math before drawing, especially when switching between vial sizes.

Used as an IGF-1 LR3 dosage calculator, the peptide calculator skips the arithmetic and returns exact syringe units, with reverse mode available for finding a water volume that lands a dose on a clean mark. For a peptide studied in a related growth-hormone-axis context, see the CJC-1295 ipamorelin dosage chart.