IGF-1 LR3 — Benefits, Dosage & Where to Buy
Research Overview
IGF-1 LR3 (Long R3 Insulin-like Growth Factor-1) is a modified version of IGF-1, the primary mediator of growth hormone's anabolic effects. The "LR3" modification involves replacing glutamic acid at position 3 with arginine and adding 13 amino acids to the N-terminus. These changes dramatically reduce binding to IGF-binding proteins (IGFBPs), resulting in a peptide with a half-life of 20-30 hours compared to ~20 minutes for native IGF-1.
IGF-1 is produced primarily in the liver in response to growth hormone stimulation. It mediates most of GH's anabolic effects on muscle, bone, and other tissues. While GH secretagogues (CJC-1295, Ipamorelin) work indirectly by stimulating GH release which then produces IGF-1, IGF-1 LR3 bypasses this entire axis and provides the end-stage growth factor directly.
This direct approach makes IGF-1 LR3 one of the most potent anabolic peptides available, but it also means it bypasses the body's natural regulatory mechanisms. Unlike GH secretagogues, IGF-1 LR3 administration can suppress endogenous GH production through negative feedback. Researchers should be aware of its potent hypoglycemic effects and proliferative activity on all cell types.
Key Research Findings
- •3-fold greater potency than native IGF-1 due to reduced IGFBP binding and extended half-life (20-30 hours vs 20 minutes)
- •Directly mediates muscle protein synthesis, satellite cell activation, and hyperplasia (new muscle cell formation)
- •Potent hypoglycemic effect — increases glucose uptake into muscle and fat cells independent of insulin
- •Proliferative effects on all cell types, including potential concerns for pre-existing tumor growth
- •Promotes both hypertrophy (cell size increase) and hyperplasia (cell number increase) — unique among anabolic agents
Research Dosage Protocols
IGF-1 LR3 is a recombinant protein requiring careful handling. It is supplied as lyophilized powder reconstituted with acetic acid or sterile water (per manufacturer specifications - check product guidelines).
Research doses are typically in the microgram range (20-100 mcg) due to its high potency. Researchers should be aware of its significant hypoglycemic effect and its non-selective proliferative activity on all cell types.
Reconstituted IGF-1 LR3 should be refrigerated at 2-8°C and used promptly. The protein is sensitive to degradation and should not be subjected to repeated freeze-thaw cycles.
For research reference only. Not medical advice. Not for human consumption.
Published Research (3 studies)
- [1]
- [2]
- [3]
Links go to PubMed (NIH National Library of Medicine). PeptideVerdict is not affiliated with these studies.
Price Comparison (16 products from 11 vendors)
| Vendor | Price | Stock |
|---|---|---|
| Paradigm Peptides | $50.00 $50.00/mg 1mg lyophilized | In Stock |
| Swiss Chems | $59.96 $59.96/mg 1mg vial | In Stock |
| Peptide Crafters | $65.00 $65.00/mg 1mg lyophilized | In Stock |
| Triumphant Labs | $82.00 $82.00/mg 1mg | In Stock |
| Polaris Peptides | $85.00 $85.00/mg 1mg lyophilized | In Stock |
| Peptide Sciences | $110.00 $110.00/mg 1mg lyophilized | In Stock |
| Biotech Peptides | $145.00 $145.00/mg 1mg vial | In Stock |
| Core Peptides | $150.00 $150.00/mg 1mg vial | In Stock |
| Pure Rawz | $47.59 $237.95/mg 0.2mg vial | In Stock |
| Peptide Sciences | $250.00 $250.00/mg 1mg lyophilized | In Stock |
| Biotech Peptides | $27.00 $270.00/mg 0.1mg vial | In Stock |
| Core Peptides | $28.00 $280.00/mg 0.1mg vial | In Stock |
| Triumphant Labs | $695.00 $695.00/mg 1mg | In Stock |
| Peptide Sciences | $300.00 $3000.00/mg 0.1mg lyophilized | In Stock |
| Apollo Peptide Sciences | $79.99 vial | In Stock |
| Skye Peptides | $99.00 lyophilized | In Stock |
Frequently Asked Questions
What is IGF-1 LR3?
IGF-1 LR3 is a modified version of IGF-1 (the main anabolic mediator of growth hormone) with a dramatically extended half-life. It provides the end-stage growth factor directly, bypassing the GH → IGF-1 production pathway.
How does IGF-1 LR3 differ from GH secretagogues?
GH secretagogues (CJC-1295, Ipamorelin) stimulate your body to produce more GH, which then produces IGF-1 naturally. IGF-1 LR3 provides the IGF-1 directly. The direct approach is more potent but bypasses natural feedback regulation.
Where can I buy IGF-1 LR3 for research?
IGF-1 LR3 is available from research peptide vendors. Compare pricing in the table above.