IGF-1 LR3 (long R3 insulin-like growth factor-1)
Muscle Building · Modified IGF-1 analog
Tier C+
What this is
Used in cell culture research, diverted for performance use. Hypoglycemia is acute and potentially severe. Chronic IGF-1 signaling activation theoretically pro-oncogenic — longevity circles argue for LOWER IGF-1 for lifespan. Counterfeits and underdosed products rampant.
Mechanism
Modified IGF-1 with Arg3 substitution and N-terminal 13-aa extension; drastically reduced IGFBP binding — longer plasma half-life and higher bioavailability than native IGF-1
Dose & route
Typical illicit: 20-50 mcg/day subQ
Citations
- https://pubmed.ncbi.nlm.nih.gov/3288649/
- https://pubmed.ncbi.nlm.nih.gov/15702321/
- https://pubmed.ncbi.nlm.nih.gov/28315373/
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This is an independent synthesis of published research by a non-clinician. Scores are opinions supported by citations, not prescriptions. See the full disclaimer and methodology for how this score was produced and what it does and doesn't mean.