How does IGF-1 LR3 differ from regular IGF-1?

IGF-1 LR3 has 13 extra N-terminal amino acids and an Arg→Glu substitution at position 3. This reduces binding to IGF-binding proteins by ~100x, resulting in a longer half-life (20-30 hours vs 12-15 hours) and approximately 3x greater potency. More of the peptide reaches target tissues in active form.

There are no formal human safety studies. Known risks include hypoglycemia, organ growth (especially intestinal), and theoretical cancer promotion via IGF-1R signaling. It is one of the higher-risk peptides due to its potent growth factor activity.

IGF-1 LR3 is a modified version of Insulin-like Growth Factor 1 with an extended half-life, researched for muscle growth and cellular proliferation.

What is the recommended dose range for IGF-1 LR3?

The research dose range is 20-100 mcg/day; research protocols commonly use 50-80 mcg/day, administered via Subcutaneous or Intramuscular, Once daily.

peptide dosing

IGF-1 LR3 Dosing & Reconstitution Guide

Complete dosing reference for IGF-1 LR3 (Growth Factor). Covers reconstitution, dose range, titration schedule, pharmacokinetics, and storage protocols for research use.

Dosing Protocol

Route: Subcutaneous or Intramuscular Frequency: Once daily Dose Range: 20-100 mcg/day; research protocols commonly use 50-80 mcg/day Cycle Length: 4-6 weeks; off-cycle recommended to prevent receptor downregulation Timing: Post-workout or morning; monitor blood glucose

Reconstitution

Vial Size: 1mg Water Volume: 1mL Concentration: 1mg/mL

Storage

Lyophilized: -20 °C (-4 °F) Reconstituted: 2-8 °C (35.6-46.4 °F) Shelf Life: 21 days

Injection Sites

Abdomen, Target muscle (IM for localized effect), Thigh

Safety & Contraindications

Safety: Hypoglycemia risk — IGF-1 has insulin-like glucose-lowering effects Potential organ enlargement with chronic use (intestinal growth observed in animals) Joint pain, water retention, carpal tunnel-like symptoms (GH/IGF axis effects)

Contraindications: Active cancer or history of cancer (IGF-1 promotes cell proliferation); Diabetes or hypoglycemia disorders; Pregnancy and breastfeeding

Peptide Tools

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Research Use Only. The information on this page is compiled from published research literature and is provided for educational purposes only. It does not constitute medical advice. All compounds referenced are intended for in vitro research use by qualified laboratories and institutions.