IGF-1 LR3

IGF-1 LR3 is a synthetic analog of insulin-like growth factor-1 (IGF-1) engineered for prolonged activity by reducing binding to IGF binding proteins and increasing half-life. IGF-1 is a key mediator of growth hormone signaling and promotes anabolic, mitogenic, and metabolic effects through IGF-1 receptor activation.

— 1 mg Vial —

Reconstitute: Add 3.0 mL bacteriostatic water → ~0.333 mg/mL concentration (333 mcg/mL).
Typical daily range: 20–50 mcg once daily subcutaneously (gradual titration recommended).
Easy measuring: At 0.333 mg/mL, 1 unit = 0.01 mL ≈ 3.33 mcg on a U-100 insulin syringe.
Storage: Lyophilized: freeze at −20 °C for up to 12 months; reconstituted: refrigerate at 2–8 °C, use within 30 days, avoid repeated freeze-thaw cycles.

Schedule: Daily subcutaneous injections for 8 weeks (standard cycle); may extend to 12 weeks.
Cycle Length: 8 weeks standard; 12-week protocols exist but may show diminished returns beyond Week 6–8.
Goal: Support anabolic processes and metabolic function through enhanced IGF-1 activity with extended bioavailability.

Frequency: Inject once daily subcutaneously, typically in the morning or post-workout with food intake to mitigate insulin-like effects on blood glucose.

• Increases anabolic signaling and muscle protein synthesis pathways (research)
• Promotes satellite cell activity and myogenic differentiation in preclinical models
• May enhance glycogen storage and nutrient partitioning
• Supports bone/connective tissue anabolic pathways (context-dependent)
• Tool compound for studying IGF-1R signaling

• Binds IGF-1 receptor (IGF-1R), a receptor tyrosine kinase
• Activates PI3K→Akt→mTOR signaling (protein synthesis, cell survival)
• Activates Ras→Raf→MEK→ERK pathway (cell proliferation/mitogenesis)
• Cross-talk with insulin receptor signaling affecting glucose uptake

• Hypoglycemia symptoms (shakiness, sweating, confusion)
• Edema/water retention
• Joint pain/carpal tunnel-like symptoms
• Headache
• Injection-site irritation
• Potential excessive tissue growth with high exposure (theoretical)
• May accelerate growth of existing malignancies (theoretical)

• Use conservative dosing; have carbohydrates available if prone to low glucose
• Monitor fasting glucose/HbA1c with longer use
• Split dosing to reduce peaks; avoid late dosing if hypoglycemia risk
• Discontinue if edema/neuropathy symptoms occur

• Active or suspected malignancy
• Proliferative diabetic retinopathy
• Uncontrolled diabetes or recurrent hypoglycemia
• Pregnancy/nursing
• Use caution with intracranial hypertension history

1. The insulin-like growth factor system in cancer. Nat Rev Cancer. PubMed | DOI
2. IGF-I receptor as a target for cancer therapy. Nat Rev Drug Discov. PubMed | DOI
3. IGF-I and muscle growth: mechanisms and implications. J Appl Physiol. PubMed | DOI
4. IGF-1 receptor signaling in skeletal muscle. Endocrinol Metab Clin North Am. PubMed | DOI