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What is IGF-1 LR3?

IGF-1 LR3 explained in plain English: what it is, what the research shows, side effects, legal status and dosage, plus a calculator for syringe units. There is no validated human dose, and this page doesn't invent one. Also called Long R3 IGF-1, LR3-IGF-1.

IGF-1 LR3 is not approved for human use by the FDA or any other regulator. This page is educational; talk with a qualified healthcare professional before using any substance.

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Vial unit

= 1,000 mcg

mL
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Syringe, no result yetU-100, 1 mL syringe holding up to 100 units. Enter your dose.0102030405060708090100

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What is IGF-1 LR3?

IGF-1 LR3 is a lab-made, modified version of IGF-1 (insulin-like growth factor 1), the hormone that carries out many of growth hormone’s effects. It has an extra 13 amino acids and one swapped amino acid that stop it sticking to the proteins that normally hold IGF-1 in check.

It was designed to help cells grow in laboratory cultures. It is sold online for muscle growth.

What does IGF-1 LR3 do?

Because it avoids IGF-1’s binding proteins, IGF-1 LR3 stays active much longer and is far more potent than natural IGF-1 in cell studies. IGF-1 signals cells to grow, divide and take up sugar.

What does the research on IGF-1 LR3 show?

All the research is in cells and animals. There are no published human trials of IGF-1 LR3, so its effects on muscle, fat or health in people are unknown.

The only approved IGF-1 medicine is mecasermin (Increlex), natural human IGF-1 for children with severe primary IGF-1 deficiency, and it is a different molecule.

IGF-1 LR3 side effects and risks

The main concern is low blood sugar, which IGF-1 can cause like insulin; Increlex carries warnings about severe hypoglycemia. Long-term overactive IGF-1 signaling has been linked to growth of tissues and, in theory, cancer risk.

Products sold online aren’t checked for purity, strength or sterility.

IGF-1 LR3 is not approved for human use anywhere. IGF-1 and its analogs are banned in sport at all times by the World Anti-Doping Agency.

How do you reconstitute IGF-1 LR3?

IGF-1 LR3 research vials hold a freeze-dried powder that is mixed with bacteriostatic water. The calculator above turns the vial size, the water and a dose into syringe units, and the reconstitution guide explains each step.

See the dosage section below for what is known about doses, with sources.

IGF-1 LR3 dosage

IGF-1 LR3 has never been tested in human trials, so there is no validated human dose. The approved IGF-1 medicine, Increlex, is a different molecule and its dosing does not apply.

There is no approved or validated human dose. This site does not repeat doses from forums, sellers or animal studies.

Medical disclaimer: this dosage information is for education only and comes from the source shown for each row. It is not medical advice and not a recommendation for you. Only a licensed prescriber who knows your health can decide whether IGF-1 LR3 is right for you and at what dose. Don't start, change or stop a medicine based on this page, and don't use research peptides or unapproved drugs based on trial doses.

IGF-1 LR3 concentration chart

The concentration of a IGF-1 LR3 vial depends only on its size and the water you add. Each unit on a U-100 syringe holds one hundredth of a mL.

IGF-1 LR3 concentration by vial size and water
Vial + waterConcentrationPer unit (U-100)
1 mg + 1 mL1,000 mcg/mL (1 mg/mL)10 mcg per unit (0.01 mg per unit)
1 mg + 2 mL500 mcg/mL (0.5 mg/mL)5 mcg per unit (0.005 mg per unit)
1 mg + 3 mL333.33 mcg/mL (0.33333 mg/mL)3.33 mcg per unit (0.00333 mg per unit)

Frequently asked questions

Is IGF-1 LR3 the same as the medicine Increlex?

No. Increlex (mecasermin) is natural human IGF-1, approved for a rare growth disorder. IGF-1 LR3 is a modified version with no approval and no human trials.

What is IGF-1 LR3 used for?

It was designed to help cells grow in laboratory cultures. Online it is sold for muscle growth, which has not been tested in people.

Is IGF-1 LR3 banned in sport?

Yes. IGF-1 and its analogs are prohibited at all times by the World Anti-Doping Agency.

Sources

  1. Wikipedia, Insulin-like growth factor 1 (with cited studies)
  2. Wikipedia, Mecasermin (Increlex), with cited label information
  3. World Anti-Doping Agency, The Prohibited List

Last updated .

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