IGF-1 LR3
Also known as: IGF-1 · Insulin-Like Growth Factor 1 · Long R3 IGF-1
A long-acting analog of IGF-1 with a modified arginine substitution that extends its half-life. Directly stimulates muscle protein synthesis independent of GH.
What is IGF-1 LR3? A long-acting analog of IGF-1 with a modified arginine substitution that extends its half-life. Directly stimulates muscle protein synthesis independent of GH.
How does IGF-1 LR3 work? IGF-1 LR3 is an 83-amino acid analog of endogenous IGF-1 that reduces its affinity for IGF-binding proteins, dramatically extending its half-life. It directly binds IGF-1 receptors in muscle and other tissues to stimulate protein synthesis.
Benefits of IGF-1 LR3: Direct muscle protein synthesis stimulation; Significant lean muscle mass increases; Enhanced fat oxidation; Improved nitrogen retention; Accelerated recovery from training; Anti-catabolic effects during caloric restriction
IGF-1 LR3 dosage: Always administer with carbohydrates to prevent hypoglycemia.
IGF-1 LR3 half-life: 20-30 hours
Research status: Research Only
Source: PeptideWiki — https://www.peptide-wiki.net/peptides/igf-1-lr3
Mechanism of Action
IGF-1 LR3 is an 83-amino acid analog of endogenous IGF-1 that reduces its affinity for IGF-binding proteins, dramatically extending its half-life. It directly binds IGF-1 receptors in muscle and other tissues to stimulate protein synthesis.
Benefits
- Direct muscle protein synthesis stimulation
- Significant lean muscle mass increases
- Enhanced fat oxidation
- Improved nitrogen retention
- Accelerated recovery from training
- Anti-catabolic effects during caloric restriction
Side Effects & Risks
- Hypoglycemia (most serious risk)
- Stomach discomfort
- Joint swelling
- Jaw pain
- Potential organ growth with excessive dosing
- Water retention
Where to Buy IGF-1 LR3
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Storage & Reconstitution Guide
Storage Temperature
-80°C long-term, -20°C up to 6 months lyophilized
24 months (lyophilized), 28 days (reconstituted)
Reconstitution Solvent
Bacteriostatic water (BAC water); always use with carbohydrates
Swirl gently — do not shake or vortex
Handling Notes
Protect lyophilized peptide from moisture and light. Once reconstituted, keep refrigerated. Discard if solution becomes cloudy or discolored. Use insulin syringe for precise dosing.
Step-by-Step Reconstitution
Gather supplies
BAC water, insulin syringe, alcohol swabs, vial
Disinfect tops
Swab rubber stoppers of both vials with alcohol
Draw BAC water
Pull desired mL of BAC water into syringe
Inject slowly
Inject BAC water down the side of the peptide vial, swirl gently to dissolve
Research Protocol
- Dose Range
- 20–100 mcg
- Frequency
- Once daily post-workout
- Cycle
- 2-4 weeks
- Half-Life
- 20-30 hours
- Routes
- subcutaneous injectionintramuscular injection
- Notes
- Always administer with carbohydrates to prevent hypoglycemia.
Legal & Regulatory Status
Sold for research purposes only. Not for human use. Laws vary by country.
Commonly Stacked With
View all peptide stacks →External Resources
Chemical Properties
- CAS Number
- 946870-92-4
- Mol. Weight
- 9,117 Da
- Formula
- C400H625N111O115S9
PeptideWiki Research Team
Evidence-based research data sourced from PubMed and ClinicalTrials.gov · Last updated: February 25, 2026
Frequently Asked Questions About IGF-1 LR3
What is IGF-1 LR3?▾
A long-acting analog of IGF-1 with a modified arginine substitution that extends its half-life. Directly stimulates muscle protein synthesis independent of GH.
What are the benefits of IGF-1 LR3?▾
Direct muscle protein synthesis stimulation
What are the benefits of IGF-1 LR3?▾
Significant lean muscle mass increases
What are the side effects of IGF-1 LR3?▾
Hypoglycemia (most serious risk)
What is the recommended dosage for IGF-1 LR3?▾
Always administer with carbohydrates to prevent hypoglycemia.
How long should a IGF-1 LR3 cycle last?▾
2-4 weeks
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