How much water do I add to IGF-1 LR3?

You can reconstitute IGF-1 LR3 with 0.5, 1, or 2 mL of bacteriostatic water. Each option produces a different concentration and syringe draw for the same dose. Use the calculator to see which is easiest to measure.

What does IGF-1 LR3 cost per dose?

Cost per dose depends on vial size, price paid, and your dose. Enter your vendor's price in the IGF-1 LR3 calculator to see cost per dose and monthly cost.

What is the reference dose for IGF-1 LR3?

The commonly referenced range is 0.02 up to 0.05 mg per day (start low, increase slowly), taken daily, cycled. This is reference information, not a recommendation. Talk to a licensed clinician.

What are the side effects of IGF-1 LR3?

Reported side effects of IGF-1 LR3 include: High risk: it can drop blood sugar dangerously, so it must never be combined with insulin, and it carries a theoretical cancer-growth concern.; Banned in drug-tested sport.. Severity and frequency vary by person and dose.

Who should not take IGF-1 LR3?

IGF-1 LR3 is generally not appropriate for: Any history of cancer, given the growth-promoting mechanism; Diabetes, or any use of insulin, because the blood-sugar drop can be dangerous; Pregnancy; Banned in drug-tested sport. Talk to a licensed clinician before starting.

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Decoding

IGF-1 LR3_Dosage, benefits & legal status

Also known as Long R3 IGF-1, LR3

By the Peptide Decoding Editorial Team

Published July 22, 2026 · Updated July 25, 2026

A powerful muscle-builder that also drops blood sugar hard.

Muscle growthIGF-1 analogResearch onlyHigh-risk

InMuscle building

Common vial size1 mg

Dose0.02 up to 0.05 mg per day (start low, increase slowly)

FrequencyDaily, cycled

RouteUnder the skin or into muscle

StatusResearch only

MixYour choice, calculate it

CycledCommonly run in 4 week blocks

Common vial size is what vendors typically sell, not a recommendation. Enter your own vial in the calculator.

What is IGF-1 LR3?

Plain language first. The technical label stays, but it never stands alone.

Overview

It directly drives muscle cells to grow and repair and stays active for hours, but it also drops blood sugar hard.

The technical version

IGF-1 LR3 is a long-acting version of insulin-like growth factor 1, the hormone that growth hormone works through to build tissue.

What it's used for

A powerful muscle-builder that drives growth in muscle cells and speeds recovery, staying active for hours.

How does IGF-1 LR3 work?

What it does in the body, and where.

IGF-1 LR3 is a modified version of the hormone that growth hormone works through, engineered to stay active far longer than the natural form.

01
It binds IGF-1 receptors on muscle cells
Driving growth and repair directly, without going through growth hormone at all.
02
The modification stops it being bound and stored
Natural IGF-1 is mostly held inactive by binding proteins. LR3 evades them, which is what makes it potent and long-lasting.
03
Blood sugar drops
IGF-1 is structurally close to insulin and acts partly like it. Hypoglycaemia is a real and immediate risk, not a theoretical one.
04
There is no human trial supporting its use for muscle
Everything is extrapolated from what IGF-1 does physiologically.

Pathway

A schematic of the compound's mechanism, not a diagnostic image.

What else is it used for?

Each use below carries its own evidence level. Approved means regulators have cleared it for that purpose. Investigational means it is in trials. Early research means it is being studied and is not established.

Driving muscle growth directlyResearch only
Speeding recovery from trainingResearch only

The published record

Research index

Records indexed for IGF-1 LR3

28 in humans, 18 of them original studies.

Browse the records

In animalsPro

In the labPro

ReviewsPro

Senior author sharePro

Counted from Europe PMC indexing, not read by a person. Human means indexed under humans, which includes reviews and work on human cells. Original studies exclude reviews and lab work on human cells.Last updated 11 September 2026.

Compound field notes

At a glance

Four things to know about IGF-1 LR3

Evidence

Research only

How much, and do you cycle it?

The range, and whether you take breaks.

0.02 up to 0.05 mg per day (start low, increase slowly), daily, cycled. Commonly run in 4 week blocksCommunity practice

The block length comes from community practice. The stated concern is that holding IGF-1 high for long periods drives growth in tissue you did not intend, and it can drop blood sugar hard. No human study establishes a schedule or a safe duration.

Compare this against the whole library →

How long does it stay in the body?

The half-life, and where the figure comes from.

Not establishedCommunity practice

The 20 to 30 hours repeated across vendor sites traces to no primary source, and animal clearance data points the other way. LR3 is built to slip past the binding proteins that hold ordinary IGF-1 in circulation, which should make it clear faster rather than slower.

Source: https://pubmed.ncbi.nlm.nih.gov/10198302/

You can compare this against the whole library to see where it sits.

How do I dose and price it?

Enter your vial and your dose. Pick a mix. We show the draw and the cost.

The vial holds a fixed amount of drug. Adding more water does not make more drug, it just spreads it thinner, so you draw a bigger number on the syringe for the same dose.

Your vial size (mg)

Printed on the vial.

What you paid per vial

Used for cost per dose only.

Your dose (mcg)

Commonly referenced range: 0.02 up to 0.05 mg per day (start low, increase slowly)Community practice

Choose your mix

0.5 mL water1units · 2 mg/mL

Half a 100-unit syringe

1 mL water2units · 1 mg/mL

One full 100-unit syringe

Easiest

2 mL water4units · 0.5 mg/mL

Two full 100-unit syringes

your own mL

units · —

Enter your own volume

Measuring the water1 mL = one full 100-unit syringe.

Your draw

4 / 100 units

4 units is a very small line to read, so a small slip is a large error. A larger water volume above spreads the same dose across more units.

Full calculator with reorder date →Read a syringe →

What it costs

IGF-1 LR3 starts at $27.00 across 44 vendors, typically $55.00 – $124.99 per mg.

59 listings, last read Sep 5, 2026. Shipping and card fees are not included.

See all 59 listings →

How do you store it?

Before mixing, and after.

Dry powder in the freezer or fridge. Once mixed, fridge, and use within about a month.

Unmixed lyophilized IGF-1 LR3 keeps for a long time cold. Once you add water the clock starts: most reconstituted vials hold up for roughly 28 to 30 days at fridge temperature. Keep it out of light, and do not freeze it after mixing.

What are the side effects and cautions?

Known cautions and warnings for this compound.

Handling note

Mixing exception: reconstitute this one with a dilute acetic acid solution, not bacteriostatic water. Plain BAC water can degrade it, so follow the product's own mixing instructions.

Who should avoid it

Check these before anything else.

Any history of cancer, given the growth-promoting mechanism
Diabetes, or any use of insulin, because the blood-sugar drop can be dangerous
Pregnancy
Banned in drug-tested sport

Stop and get help

These are emergencies. Seek care.

Signs of very low blood sugar such as shaking, sweating, confusion, or fainting, which needs fast-acting sugar and urgent help
New lumps or masses
Severe headaches or vision changes
Signs of an allergic reaction such as face or throat swelling, hives, or trouble breathing

Common effects

Expected, and usually mild.

Low blood sugar, which is the main and most dangerous effect
Injection-site reactions
Joint pain
Water retention

Where this page says nothing is established, that means nobody has studied it, not that a compound is safe.

Is IGF-1 LR3 approved?

And where the numbers on this page come from.

No. IGF-1 LR3 is not approved for any use, anywhere. It is sold labelled for laboratory research only, and there is no legal route to buy it for human use.

Approval status
Research only
Route
Under the skin or into muscle
Checked
September 2026

What has happened recently

Not approved for any use. The low-blood-sugar risk is the practical danger, and it is the reason combining it with insulin is described as dangerous.

Banned in drug-tested sport. Most research peptides are prohibited under WADA's S0 category, which covers any substance with no approval from any regulatory authority for human use. That means a compound can be banned without ever being named on the prohibited list. Check with your own anti-doping authority rather than assuming absence from the list means permitted.

You can compare this against the whole library, or read how to check a seller.

DoseFrom research and community reports. No regulator has reviewed this dose.
Vial sizeFrom what vendors typically list; not a recommendation.
Sources
Clearance of IGFs and insulin from wounds: effect of IGF-binding protein interactions Tomas et al., Superior potency of infused IGF-I analogues which bind poorly to IGF-binding proteins, Journal of Endocrinology
Reviewed8 September 2026

What else is like IGF-1 LR3?

Others in Muscle building, side by side.

If you're weighing IGF-1 LR3, it's worth reading IGF-1 DES, Follistatin (FST-344), and MGF (Mechano Growth Factor) in the same class.

YOU ARE HERE

LR383 residues

IGF-1 LR3

A powerful muscle-builder that also drops blood sugar hard.

Research only

Dose: 0.02 up to 0.05 mg per day (start low, increase slowly)
How often: Daily, cycled

DES

IGF-1 DES

A short-acting muscle-builder that works right where you inject it.

Research only

Dose: 0.05 up to 0.15 mg per dose (start low, increase slowly)
How often: Around training

FST

Follistatin (FST-344)

An experimental muscle-builder that releases the body's brake on growth.

Research only

Dose: Research only
How often: Cycled

MGF

MGF (Mechano Growth Factor)

A local muscle-repair peptide injected near a worked muscle.

Research only

Dose: 0.1 up to 0.2 mg per dose (start low, increase slowly)
How often: Post-workout

Browse the full muscle-building lineup

Compared with

IGF-1 LR3 vs IGF-1 DES

Neither has a single published human trial, and sources give LR3's half-life as anywhere from 6 to 30 hours. There is an FDA approved IGF-1, and it is neither of these.

Read comparison →

Guides for this compound

How to Reconstitute a Peptide
Mix peptide powder with bacteriostatic water, step by step.
How to Read an Insulin Syringe
Read the units, convert to millilitres, and draw the exact dose.
mcg vs mg: The Peptide Dosing Mistake to Avoid
Your vial says mg and your protocol says mcg. Here is the conversion and how to check it.
Why Does My Peptide Injection Itch or Welt
Injection-site irritation, a histamine reaction, or a true allergy, and how to tell them apart.
How to Read a Peptide COA
What the purity number does and does not tell you, and how to spot an edited report.

Sources

Clearance of IGFs and insulin from wounds: effect of IGF-binding protein interactions(1999)
In rat wound chambers, LR3-IGF-I cleared faster than ordinary IGF-I, not slower. Half-lives were 872 minutes for IGF-I and 563 minutes for LR3-IGF-I. This is the opposite direction to the 20 to 30 hour figure repeated on vendor sites.
Tomas et al., Superior potency of infused IGF-I analogues which bind poorly to IGF-binding proteins, Journal of Endocrinology(1996)
The source usually cited for LR3 potency. Poor binding-protein affinity is what makes the analogue more potent, and it is also what should shorten its time in circulation.

Last reviewed 8 September 2026

Beyond these, 91 records are indexed. Browse the records