IGF-1 LR3
IGF-1 LR3 (Long R3 Insulin-like Growth Factor-1) is a modified version of IGF-1 with extended half-life and enhanced potency. The modifications prevent binding to IGF binding proteins, increasing bioavailability.
Mechanism of Action
Binds to IGF-1 receptors to promote protein synthesis, muscle growth, and fat metabolism. The LR3 modification (13 amino acid extension and arginine substitution) extends half-life from minutes to 20-30 hours.
Dosage Overview
Dose Range
20 mcg – 100 mcg
Route
subcutaneous
Frequency
1x daily
Cycle Length
4–6 weeks
Reconstitution
Typical Dosage (Research)
Research protocols typically use 20-100mcg daily, often divided into multiple injections or administered bilaterally to target muscles.
Intramuscular injection (site-specific growth) or subcutaneous for systemic effects. Often cycled 4-6 weeks on, equal time off.
Considerations for Men & Women
Women: IGF-1 levels are influenced by estrogen status — premenopausal women naturally have different IGF-1 dynamics than postmenopausal women. Potent growth factor; contraindicated during pregnancy. May affect menstrual regularity at higher doses.
Men: Often used in muscle growth research. Testosterone can synergize with IGF-1 signaling. Hypoglycemia risk exists for both sexes — always use with food. Monitor for joint pain and edema.
Individual responses vary. These notes reflect general trends from research literature and are not medical advice.
Quick Calculator
Concentration: 1 mg/ml
Volume to inject: 0.02 ml
Syringe units (U-100): 2.0 units
Pre-filled with IGF-1 LR3 defaults. Adjust values as needed.
Side Effects & Risks
Hypoglycemia, joint pain, water retention, potential jaw/hand growth with extended use, and injection site reactions.
May promote growth of existing tumors. Can cause significant hypoglycemia. Long-term effects on insulin sensitivity concerning.
Who Uses IGF-1 LR3
Bodybuilders seeking muscle growth, those in aggressive recovery protocols.
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