PEPTIDE CORTEXThe library
← The library

IGF-1 LR3

researchMuscle/Performance
Evidence grade
DResearch/compounded/adjunct (no established FDA indication)
Cardiovascular · 0–5 · separate axis
1
Read first · not dosing instructions

Educational and research reference only. Not medical advice, not a recommendation, and not dosing instructions for any person. Figures are reported from the cited source and may be wrong or out of date. Research peptides are not approved for human use. Adults 18+. Consult a licensed physician before any decision about your health.

PurposeMuscle / Performance
MechanismLong-acting IGF-1 analog with reduced binding-protein affinity, extending activity well beyond native IGF-1
EffectsDrives tissue growth signalling directly rather than via the GH axis; can affect blood sugar
DosingNo human dose established.
Bottom linePopular in research/compounding; human safety/benefit not well-established.
Protocols · as published1 sourced
Community protocol — not clinically establishedCommunity guide
RouteSubcutaneous or intramuscular
FrequencyOnce daily
Starting20 mcg/day ("used to gauge tolerance and hypoglycemic response")
EscalationLow 20-40 mcg/day; moderate 40-80; high 80-100 mcg/day
Target40-60 mcg/day; "diminishing returns commonly reported above ~50-60 mcg/day"
CycleStandard 4 weeks on / 4 off minimum; "Continuous, multi-month use is widely discouraged"

No published human trial of IGF-1 LR3. Hypoglycaemia is the principal acute risk; the guide says "Never pre-bed".

Batches on filenone

No tested batches on file.

Read with10
Cautions & interactions

Not FDA-approved; avoid self-administration; unverified sourcing and purity

No well-established interaction profile for non-approved peptides; avoid combining multiple research compounds; discuss meds with clinician.

CV 1 of 5 — No cardiovascular outcomes data; growth-factor signalling carries theoretical proliferative concerns.