How do I reconstitute IGF-1 LR3?

Concentration equals vial size divided by the bacteriostatic water added, and units on a U-100 syringe equal draw volume in millilitres times 100. Common vial sizes for IGF-1 LR3 are 0.1 mg (100 mcg).

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Protocol Reference

Animal data only

IGF-1 LR3 protocol

IGF-1 LR3 (Long R3 insulin-like growth factor 1). The published work on this compound is animal or cell-culture research. No human dosing schedule exists to cite.

PepGuru Research Team·Reviewed Aug 2026

How IGF-1 LR3 works

An IGF-1 analog with an arginine substitution at position 3 and a 13-amino-acid N-terminal extension. Those changes sharply reduce binding to IGF binding proteins, leaving more of it free and active — which is also why it is more potent than native IGF-1.

IGF-1 LR3 dosing — what the literature actually supports

Animal data only. This distinction matters and is routinely blurred: recombinant human IGF-1 (mecasermin, marketed as Increlex) is an approved drug with a real label for severe primary IGF-1 deficiency. IGF-1 LR3 is a different, more potent analog developed largely as a cell-culture reagent, and it has no human approval, no human trial and no citable human schedule. A mecasermin figure is not an LR3 figure, and the reduced binding-protein affinity means the two are not interchangeable at the same number.

We publish a schedule when there is a citable human source and we say so when there is not. Filling this space with a number nobody measured would make the page look more complete and be worth less than nothing to you.

Reconstitution and measurement

This part is arithmetic and does not depend on the evidence level. Concentration is vial size divided by the bacteriostatic water you add. Draw volume is your target amount divided by that concentration. Units are draw volume times 100, because a U-100 syringe reads 100 units per millilitre. Common vials for IGF-1 LR3: 0.1 mg (100 mcg).

Open the IGF-1 LR3 calculator → Unit converter

Storage and stability

Dry powder

Cold, dark and dry. Lyophilized peptide is the stable form — keep it that way until you intend to use it.

After reconstitution

Refrigerate at 2–8 °C, protect from light, and plan around a limited window. Do not freeze a reconstituted vial — freeze-thaw damages peptides.

Mixing

Run bacteriostatic water down the inside wall of the vial rather than onto the powder, then swirl. Never shake.

Inspect before use

A clear solution is expected. Cloudiness or particles mean discard, not use.

Full storage guide → · Cloudy solution?

Reported effects

No human trial safety data for the LR3 analog.
Hypoglycaemia is the mechanistically predictable risk for any IGF-1 agonist, and is a labelled warning for mecasermin.
LR3 is widely sold as a laboratory cell-culture reagent, which is the use its manufacturing is qualified for.

Sourcing IGF-1 LR3

Whatever you are working with, the documentation matters more than the price. Ask for a batch certificate of analysis whose lot number matches the vial you actually receive — a COA for a different batch tells you nothing about yours.

IGF-1 LR3 at Summit Research Supply → Grade a COA first

Summit is the supplier we feature and an affiliate link. Our COA checklist applies the same way to any vendor.

Sources and further reading

For laboratory research use only. This page documents what the published literature reports about IGF-1 LR3. It is not a recommendation, not a treatment plan, and not medical advice. Compounds referenced are sold strictly as research chemicals and are not for human or veterinary use. Some supplier links are affiliate links and may earn us a commission. This never affects tier placement or review conclusions.