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IGF-1 LR3

Growth HormoneResearch Onlymoderate evidence
FM

Reviewed by Fat Man in the Arena · Updated March 2026

Key Takeaway

IGF-1 LR3 is a modified version of insulin-like growth factor 1 with a longer half-life, promoting muscle growth and recovery.

How it works

Binds to IGF-1 receptors to promote protein synthesis, cell growth, and inhibit cell death. The LR3 modification extends half-life from minutes to 20-30 hours.

Benefits

  • Enhanced muscle growth
  • Improved recovery
  • Cell proliferation

Side effects

  • Hypoglycemia risk
  • Joint pain
  • Organ growth concerns with prolonged use

Dosing protocol

Typical Dose

20-50 mcg daily

Frequency

Once daily

Cycle Length

4-6 weeks

Use with caution. Monitor blood sugar.

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Medical Disclaimer: This content is for informational and educational purposes only. It is not intended as medical advice or a substitute for professional medical consultation, diagnosis, or treatment. Always consult a qualified healthcare provider before starting any peptide protocol.