Epitalon vs IGF-1 LR3

Side-by-side comparison of mechanisms, dosing, interactions, and stacking potential.

EpitalonIGF-1 LR3
CategoryGrowth FactorsGrowth Factors
Standard DoseResearch indicates 20-50 mcg daily via subcutaneous or intramuscular injection.
TimingPost-workout administration for muscle growth. Can be injected locally (intramuscularly) into target muscle groups. Morning dosing on rest days.
Cycle Duration4-6 week cycles maximum. Longer cycles risk significant side effects and receptor desensitization.
Evidence LevelEmergingmoderate_human
A

Epitalon

Growth Factors

Mechanism

Synthetic tetrapeptide studied in Russian longevity literature for pineal signaling, circadian regulation, and telomerase-related hypotheses.

Contraindications

  • Human evidence remains limited
B

IGF-1 LR3

Growth Factors

Mechanism

IGF-1 LR3 (Long Arginine 3-IGF-1) is an 83-amino acid synthetic analog of IGF-1 with an arginine substitution at position 3 and 13 additional N-terminal amino acids. These modifications eliminate binding to IGF-binding proteins, making it approximately 3x more potent than native IGF-1 with a half-life of 20-30 hours (vs 12-15 minutes for native IGF-1). It activates the IGF-1R tyrosine kinase receptor, triggering IRS-1/PI3K/Akt/mTOR and PI3K/Akt/GSK3-beta pathways to drive protein synthesis, muscle hypertrophy, and hyperplasia (new muscle cell formation).

Standard Dosing

Research indicates 20-50 mcg daily via subcutaneous or intramuscular injection.

Timing

Post-workout administration for muscle growth. Can be injected locally (intramuscularly) into target muscle groups. Morning dosing on rest days.

Cycle Duration

4-6 week cycles maximum. Longer cycles risk significant side effects and receptor desensitization.

Side Effects

  • Hypoglycemia (primary danger — can be severe)
  • Organ and intestinal growth with chronic use
  • Joint pain
  • Jaw/hand growth (prolonged use)
  • Increased tumor risk
  • Water retention
  • Neuropathy

Contraindications

  • Active cancer or history of cancer (IGF-1 is a potent growth factor for tumors)
  • Diabetic retinopathy
  • Pregnancy and breastfeeding
  • Acromegaly features
  • Under 25 years of age (growth plate concerns)

Best Stacking Partners

HGHMGFPEG-MGF

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