PubMed
Insulin-like growth factor-I and its binding proteins in sport and exercise medicine
Baxter, 2011
Long R3 IGF-1
IGF-1 LR3 (Long R3 Insulin-like Growth Factor-1) is a recombinant analog of IGF-1 with an Arg3 substitution and a 13-amino acid N-terminal extension. These modifications dramatically reduce binding to IGF-binding proteins (IGFBPs), resulting in a ~20–30 hour half-life (vs. 12–15 hours for native IGF-1) and significantly greater tissue exposure and anabolic potency. Research only; not FDA-approved.
Overall check-ins
Trackers & reports
Overview
IGF-1 LR3 (Long R3 Insulin-like Growth Factor-1) is a recombinant analog of IGF-1 with an Arg3 substitution and a 13-amino acid N-terminal extension. These modifications dramatically reduce binding to IGF-binding proteins (IGFBPs), resulting in a ~20–30 hour half-life (vs. 12–15 hours for native IGF-1) and significantly greater tissue exposure and anabolic potency. Research only; not FDA-approved.
Community
From check-in ratings — separate from side effects logged below. Side effects are logged separately from overall experience. A favorable check-in can still include nausea, fatigue, or injection-site reactions.
Favorable 97% · Mixed 3% · Unfavorable overall 0%
Benefits users selected when logging a favorable or mixed check-in.
Side effects are logged separately from overall experience. A favorable check-in can still include nausea, fatigue, or injection-site reactions.
Median bucket: 50–100 mcg · Most common: 10–25 mcg
Reports span 0–200 mcg
Anonymized self-reports from PeptIQ users — not prescribing guidance. Buckets group similar logged amounts; open-ended top buckets mean “at least” that dose.
Among repeat reporters, 96% said they felt similar to their last entry, 4% more positive, and 0% more negative.
Overall, repeat reporters leaned more positive than their previous entry.
Median gap between entries: 153 days · Based on 28 repeat reporters
Research
PubMed
Baxter, 2011
ClinicalTrials.gov
ClinicalTrials.gov, 2024
PubMed
Engel et al., 2025
PubMed
Yavuz et al., 2025
Tools
More ways to learn about IGF-1 LR3 from observational PeptIQ data.
Compare with
Related peptides
Help
This page summarizes 30 anonymized self-reports from PeptIQ users who track IGF-1 LR3, including commonly reported effects and co-tracked peptides. These are observational patterns, not clinical outcomes.
PeptIQ separates overall check-in ratings (favorable, mixed, or unfavorable) from logged side effects like nausea or fatigue. Users often report benefits and side effects in the same check-in — a high experience score does not mean zero side effects were noted.
4 sources are linked on this page, including PubMed articles, clinical trial registries, and FDA labels where applicable. Citations describe published research — not recommendations.
This wiki does not assess safety or recommend use. IGF-1 LR3 is listed as Research Only. Consult a licensed clinician for personal medical decisions.
This wiki summarizes observational community reports and linked citations for IGF-1 LR3. It does not assert therapeutic benefits. See the cited research list on this page and the educational profile for IGF-1 LR3 for study-level context — not medical advice.
IGF-1 LR3 is listed in PeptIQ as Research Only. Regulatory status varies by jurisdiction and can change. This wiki does not provide legal advice; check current FDA and local rules and talk with a licensed clinician or counsel for personal decisions.
Safety data quality for IGF-1 LR3 varies widely by compound and study design. PeptIQ does not establish a risk profile here. Review primary literature, product labeling where applicable, and clinician guidance. Community self-reports are not a substitute for clinical evidence.
This page links 4 indexed sources for IGF-1 LR3. Evidence maturity differs by application — some peptides have large human programs, others are mostly preclinical. Treat citation counts as literature volume, not proof of efficacy.