IGF-1 LR3 is a modified version of insulin-like growth factor 1 (IGF-1) with an extended N-terminal sequence (13 additional amino acids) and an arginine-to-glutamic acid substitution at position 3. These modifications dramatically reduce binding to IGF-binding proteins (IGFBPs), resulting in a half-life of 20-30 hours (vs 12-15 hours for native IGF-1) and approximately 3x greater potency. It is one of the most potent anabolic peptides available and is WADA-banned.
Typical dose
20-100mcg (research range) Once daily
Once daily
Route
Subcutaneous
Administered via subcutaneous or intramuscular injection once daily. Some research protocols time injections post-exercise for localized effects. Bilateral injection (split between muscle groups) is used in some protocols.
Cycle
4-6 weeks maximum Typical duration
Typical duration
Storage
-20°C to -80°C (lyophilized) Refrigerated
Follow vendor guidance
Marketplace
11 offers for IGF-1 LR3
| Vendor | Price | Rating | Shipping | COA | Action |
|---|---|---|---|---|---|
LA Peptides
| $59.99 $59.99/mg | No reviews | 2–5 days United States | None | |
Trulab Peptides
| $63.00 $63.00/mg | No reviews | 2–5 days Worldwide | None | |
prpeps
| $65.00 $65.00/mg | No reviews | 2 days United States | None | |
Vertex Labs
| $69.00 $99.00 $69.00/mg −30.3% | No reviews | 3 days United States | None | |
Amino Club
| $69.99 $69.99/mg | No reviews | 1–4 days United States | None | |
Bionova Peptides
| $70.00 $139.99 $70.00/mg −50% | No reviews | 1–3 days United States | None | |
Synthesis Peptides
| $78.99 $78.99/mg | No reviews | 2–5 days United States | None | |
American Peptides
| $85.00 $85.00/mg | No reviews | 1-2 days United States | None |
What the research reports
Outcomes described across the published literature and ongoing study, not promised results. Read each as research context, not a personal guarantee.
Muscle growth research
Cellular proliferation
Recovery
Dosage and protocol
to minutes for native IGF-1). Research protocols typically use 20-80mcg per day administered subcutaneously. Cycles are kept short (4-6 weeks) with mandatory breaks to prevent receptor desensitization.
01 Route
Subcutaneous, Intramuscular
02 Example range
40-60mcg
03 Frequency
Once daily
04 Timing
Administered via subcutaneous or intramuscular injection once daily. Some research protocols time injections post-exercise for localized effects. Bilateral injection (split between muscle groups) is used in some protocols.
Educational reference only. Use clinician guidance for dosing decisions.
Evidence
Intranasal LR3 IGF-1 remodeled amyloid plaques but did not preserve cognitive function in 5XFAD mice.
IGF-1 LR3 did not promote growth in late-gestation growth-restricted fetal sheep.
Decellularized nerve conduit with GelMA and controlled IGF-1 LR3 release enhanced rat sciatic nerve regeneration.
Acute IGF-1 LR3 infusion reduced glucose-stimulated insulin secretion in fetal sheep but effect did not persist in isolated islets.
IGF-1 infusion increases fetal organ growth independently of nutrient transfer mechanisms.
Interactions
IGF-1 LR3 + TB-500
Often discussed together in recovery-focused research stacks.
IGF-1 LR3 + GHK-Cu
Sometimes paired in tissue and skin research conversations.
FAQ
IGF-1 LR3, also searched as IGF1 LR3 or Long R3 IGF-1, is a modified insulin-like growth factor analog with an extended half-life, researched for muscle growth and cellular proliferation.
Pep Grading
United States