PeppiLibrary

Growth Hormone

IGF-1 LR3 peptide reference

Long-acting IGF-1 analog. Direct anabolic signaling at IGF-1 receptors.

Last reviewed May 6, 2026 Human data Not FDA approved
Peppi reviewing IGF-1 LR3 notes
Default dose label30 mcg
Preferred routeSubQ
Frequency label1× daily
Storage window14 days mixed

Evidence snapshot

Human data

Evidence maturityHuman data
Animal studies and limited human use; not approved for human therapy

Research chemical (US)

Route map

How records are usually labeled

1 SubQ
2 IM

Localised injection near worked muscles is anecdotal — systemic effect is similar regardless of site.

Vial timeline

Storage cues to log

Before mixRefrigerate 2–8 °C; freeze for long-term.
After mixRefrigerate 2–8 °C, use within 14 days; some users prefer 0.6% acetic acid for stability.
Use-by cue14 days after mixing
Mixed vial window14 days
Use this as a record-keeping cue, not a replacement for product labeling.

Peppi workflow

From vial to review

Vial 1 mg vial
Dose 30 mcg
Route SubQ
Review 14d storage

Peppi turns scattered dose, vial, route, storage, note, and report details into one record trail.

Educational reference only

This page helps you understand what to track for IGF-1 LR3. It is not medical advice, a prescription, or a recommendation to use this peptide. Discuss dose, route, timing, storage, and safety with a qualified healthcare professional.

Overview

IGF-1 LR3 is a synthetic 83-amino-acid analog of insulin-like growth factor 1, modified with a 13-residue N-terminal extension and an arginine-for-glutamic-acid substitution at position 3. The modifications dramatically reduce IGFBP binding, freeing more active IGF-1 in circulation and extending the effective half-life from minutes to ~20–30 hours.

Also known as: Long R3 IGF-1, LR3 IGF-1.

Hypertrophy supportRecovery researchDirect IGF-1 signaling vs indirect via GH

Mechanism and timing snapshot

Activates IGF-1 receptors on skeletal muscle, bone, and other tissues. Reduced binding to IGFBPs prolongs free-IGF-1 half-life vs native protein.

Onset labelNot listed
Catalog onset field, when available.
Half-life label24 hr
~20–30 hours (vs ~10 minutes for native IGF-1)
Duration label30 hr
Catalog duration field, when available.
subQ High
oral Negligible

Tracking defaults

These values come from Peppi's catalog so records can be prefilled consistently. They should be reviewed against your clinician's instructions before logging real-world use.

Catalog default dose30 mcg
Catalog dose range20 mcg - 60 mcg
Default routeSubQ
Frequency label1× daily
Best time labelPre or post-workout; or morning if not training that day.
Food noteCarbs post-injection support anabolic effect.

Catalog protocol note

20–50 mcg subQ once daily, often pre- or post-workout. 4–6 week cycles.

Routes and site notes

Available route labelsSubQ, IM
Preferred route labelSubQ
Common site labelsAbdomen, Near worked muscle (some users)
Site rotation noteLocalised injection near worked muscles is anecdotal — systemic effect is similar regardless of site.

Chemistry

SequenceModified IGF-1 with 13-AA N-terminal extension; Arg→Glu at position 3
Amino acids83
Molecular formulaC400H625N111O115S9
Molecular weight9111.5 Da

Vial, reconstitution, and storage

Supply formLyophilized powder
Typical vial size1 mg
DiluentBacteriostatic water (or acetic acid 0.6% per some labs for stability)
Diluent volume1 mL
Concentration note1 mg in 1 mL → 0.03 mL = 30 mcg (3 units on a 100-unit insulin syringe).
Before reconstitutionRefrigerate 2–8 °C; freeze for long-term.
After reconstitutionRefrigerate 2–8 °C, use within 14 days; some users prefer 0.6% acetic acid for stability.
Reconstituted shelf life14 days
Light sensitiveYes
Freeze/thaw warningYes

Safety notes

Common and rare side effects listed in the catalog

  • Hypoglycemia (~30 min after dose)
  • Mild fatigue
  • Headache
  • Joint pain
  • Carpal tunnel symptoms
  • Edema

Contraindications and warnings

  • Active malignancy (concerning — IGF-1 is mitogenic)
  • Diabetic retinopathy
  • Pregnancy
  • Not FDA-approved.
  • Mitogenic activity raises theoretical cancer concerns with chronic use.
  • Hypoglycemia risk is real — eat carbs after injection.

Other considerations

  • Always have fast carbs available when dosing — hypo risk is genuine.
  • Long-term safety in healthy users is poorly characterised.

Evidence and regulatory context

Evidence levelAnimal studies and limited human use; not approved for human therapy
FDA approvedNo
Regulatory statusResearch chemical (US)
Prescription requiredNo
Approved countriesNot listed

Stacking and cycle notes

Stacks well withNot listed
Avoid combining noteInsulin, Other anabolic peptides without clinician oversight
Typical cycle label4
Typical break label4–8
Cycle guidanceShort cycles only. Receptor downregulation and theoretical cancer concerns argue against long continuous use.

Tracking tips

  • Eat carbs post-injection — hypoglycemia risk is real.
  • Short cycles (4 weeks max) are the consensus due to receptor downregulation.
  • Banned in competitive sports — WADA prohibited.

References

Track it in Peppi

Keep IGF-1 LR3 records organized.

Use Peppi for dose logs, vial inventory, storage dates, reminders, journal notes, photos, and clinician-ready reports.

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FAQ

What should I track for IGF-1 LR3?

Track the peptide name, dose amount and unit, route, vial label, timing, reconstitution or expiration dates, storage notes, and any symptoms or questions for clinician review.

Does Peppi tell me how to use IGF-1 LR3?

No. Peppi organizes educational reference and your own records. Protocol decisions should come from a qualified healthcare professional.

Can I export IGF-1 LR3 records?

Peppi is designed to keep dose logs, vial inventory, journal notes, and reports easier to review and export.

Last reviewed: May 6, 2026