IGF-1 LR3 vs Cortexin

A detailed comparison to help you understand the differences and choose the right peptide for your research goals.

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.

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Cortexin

Cortexin is a polypeptide complex derived from pig brain cortex, used clinically in Russia and Eastern Europe for neurological conditions including stroke recovery, traumatic brain injury, and cognitive decline.

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Side-by-Side Comparison

AspectIGF-1 LR3Cortexin
MechanismBinds 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.Contains a mixture of neuropeptides and amino acids that support neuronal metabolism, provide neuroprotection, and enhance synaptic transmission. Specific mechanisms not fully characterized.
Typical DosageResearch protocols typically use 20-100mcg daily, often divided into multiple injections or administered bilaterally to target muscles.Clinical protocols: 10mg intramuscularly once daily for 10-20 days. May be repeated after 3-6 month interval.
AdministrationIntramuscular injection (site-specific growth) or subcutaneous for systemic effects. Often cycled 4-6 weeks on, equal time off.Intramuscular injection. Comes as lyophilized powder requiring reconstitution. Treatment given in courses rather than continuously.
Side EffectsHypoglycemia, joint pain, water retention, potential jaw/hand growth with extended use, and injection site reactions.Generally well-tolerated. May cause injection site reactions or mild allergic responses in sensitive individuals.
Best For

What They Have in Common

Both IGF-1 LR3 and Cortexin are commonly used for:

Key Differences

Unique to IGF-1 LR3:

Unique to Cortexin:

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