Growth Factor injectable

IGF-1 LR3

By Hack SmithLast updated: How we research

Promotes prolonged muscle growth and recovery

Common Uses
  • Muscle Growth
  • Fat Loss
  • Recovery
Evidence Grade
C — Limited — Animal study data
Animal study data available. No human trial data.
Safety Notes

SERIOUS HYPOGLYCEMIA RISK: IGF-1 LR3 can cause dangerous blood sugar drops, especially at high doses. Never use without glucose monitoring and emergency carbohydrate availability. NO HUMAN CLINICAL TRIALS: Safety data comes primarily from animal studies; human adverse effect profile is largely unknown. POTENTIAL ONCOGENIC CONCERN: IGF-1's growth-promoting pathways (ERK/PI3K) may theoretically promote tumor growth with prolonged use.

Mechanism of Action

IGF-1 LR3 is a modified analog of insulin-like growth factor 1 with an extended N-terminus (13 amino acids) that dramatically reduces binding to IGF binding proteins (IGFBPs), resulting in a longer half-life and greater bioavailability than native IGF-1. It activates the IGF-1 receptor (IGF1R), triggering downstream signaling primarily through the ERK (extracellular signal-regulated kinase) and PI3K (phosphoinositol-3 kinase) pathways, which regulate cell proliferation, survival, and protein synthesis. Key Pathways: IGF-1 receptor (IGF1R) activation, ERK/MAPK signaling cascade, PI3K/Akt pathway, Myoblast proliferation and differentiation The ERK and PI3K pathways activated by IGF-1 LR3 stimulate cell division and tissue growth, which in animal studies manifests as increased organ weights (heart, spleen, adrenal) and enhanced myoblast proliferation in skeletal muscle. The extended half-life due to reduced IGFBP binding theoretically allows for more sustained anabolic signaling compared to native IGF-1, though this has not been confirmed in human trials.

Common Dose Reference Ranges

Educational reference ranges only — discuss actual dosing with a qualified healthcare provider.

Low
20
mcg
Standard
60
mcg
High
100
mcg
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Full IGF-1 LR3 protocols — frequency, timing, cycle length, reconstitution & research

Frequency: Daily
Half-life: 20-30 hours
Cycle length: 4 weeks
Side Effects
  • Hypoglycemia
  • Reduced Glucose-Stimulated Insulin Secretion
  • Altered Amino Acid Metabolism
  • Soft Tissue Growth/Organ Enlargement
  • Injection Site Reactions
  • Theoretical Cancer Risk
  • Potential Pancreatic Islet Dysfunction
Compatible Stacks
Growth Hormone (HGH)TestosteroneInsulinMK-677 (Ibutamoren)BPC-157
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