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Peptide Library / Growth Hormone / Performance

IGF-1 LR3

Long R3 Insulin-like Growth Factor-1

IGF-1 LR3 Research Protocol

Complete Research Guide 4 min read1 peer-reviewed references

Quickstart Overview

IGF-1 LR3 (Long R3 IGF-1) is a modified insulin-like growth factor-1 with an arginine substitution at position 3 and a 13-residue N-terminal extension. These changes reduce binding to IGF-binding proteins, giving a much longer half-life and potent anabolic signalling.

Reconstitution
Add 1.0 mL bacteriostatic water to a 1 mg vial → 1 mg/mL
Literature Range
20–80 mcg per day
Measuring Reference
At 1 mg/mL: 40 mcg = 0.04 mL = 4 units
Frequency
Once daily
Route (studies)
Subcutaneous
Half-life
~20–30 h

Scientific Data

Molecular Formula
—
Molecular Weight
9111 Da
Sequence
Arg3, Glu3 extended IGF-1
Sequence Length
17
CAS
Research compound
Peptide Family
IGF analog
Half-life
Refer to published literature
Solubility
Bacteriostatic water, sterile saline
Storage
Lyophilized: -20°C. Reconstituted: 2–8°C, use within 2–4 weeks.
Appearance
White lyophilized powder
Standard: 1 mg vial · 1 mL diluent

Dosing & Reconstitution Guide

Interactive Reconstitution
Adjust vial size, diluent and target dose. Results update live.
Full Precision Calculator →
Concentration
1.00 mg/mL
Draw Volume
0.040 mL
Syringe Units
4.0 U
Doses / Vial
25

Units assume a U-100 insulin syringe (100 units = 1 mL). Keep fast carbs on hand — IGF-1 analogs can cause hypoglycaemia.

Frequency: Once daily

Reconstitution Steps

  1. 1Allow the lyophilized vial and bacteriostatic water to reach room temperature (~15 min).
  2. 2Swab both vial stoppers with a fresh 70% isopropyl alcohol pad and let them dry.
  3. 3Draw 1.0 mL of bacteriostatic water into a mixing syringe.
  4. 4Insert at an angle and let the water run slowly down the glass wall — never directly onto the powder.
  5. 5Gently swirl (do not shake) until the solution is completely clear.
  6. 6Label with date and concentration (mg/mL) and refrigerate at 2–8 °C immediately.

Supplies Needed

Planning example for a 4-week protocol at approximately 40 mcg per day.

Peptide (1 mg vials)
Estimate vials from total mass: 40 mcg/day × 28 days.
Bacteriostatic Water
One 10–30 mL vial typically covers a full cycle.
Insulin Syringes (U-100)
One per administration (29–31 G, 0.3–0.5 mL).
Alcohol Swabs
Two per administration (vial + site).
Sharps Container
Required for safe disposal.

Protocol Overview

Goal
Model sustained IGF-1-receptor anabolic signalling.
Schedule
Daily, 4 weeks on / 4 off.
Dose Range
20–80 mcg/day.

Dosing Protocol

Start
20–40 mcg once daily
Target
40–80 mcg/day
Frequency
Once daily, often post-training
Cycle Length
4 weeks on, 4 off (receptor sensitivity)
Timing
Post-workout; monitor for hypoglycaemia
Route
Subcutaneous

Storage Instructions

Lyophilized
−20 °C long term (18–24 months); stable at room temperature for short transit.
Reconstituted
2–8 °C refrigerated; use within 4 weeks.
Light
Protect from direct light; keep in the original carton.
Freeze/Thaw
Avoid repeat freeze–thaw cycles after reconstitution.

Important Notes

  • Hypoglycaemia is the acute safety concern.
  • Cycle to preserve receptor sensitivity.
  • Theoretical neoplasia concern with any growth factor.

How This Works

IGF-1 LR3 binds the IGF-1 receptor to activate the PI3K/Akt and MAPK pathways that drive protein synthesis, cell proliferation and hyperplasia. Because the R3 modification lowers affinity for IGF-binding proteins, far more free peptide is available and its half-life extends to ~20–30 hours (versus minutes for native IGF-1), producing sustained anabolic activity. It also promotes nutrient uptake and glucose metabolism.

Potential Benefits & Side Effects

Reported in research
  • Potent, sustained anabolic signalling (PI3K/Akt)
  • Muscle-cell hyperplasia and protein synthesis in models
  • Long half-life vs native IGF-1
  • Enhanced nutrient partitioning and glucose uptake
Possible considerations
  • Hypoglycaemia risk (keep fast-acting carbs available)
  • Potential for growth of all tissues — theoretical neoplasia concern
  • Injection-site reactions
  • Organ growth at high chronic doses (animal data)

Lifestyle Factors

  • Adequate hydration and 7–9 h of sleep are standard controls in most research protocols.
  • Consistent dose timing improves the reliability of any self-tracked endpoints.
  • Maintain a clean, sterile workflow for every draw to avoid contamination.

Injection Technique

  1. 1Wash hands, then prep the vial top and the target site with separate alcohol swabs.
  2. 2Pinch a subcutaneous skin fold (abdomen, ~2 inches from the navel) and insert at 45–90°.
  3. 3Depress the plunger slowly over 3–5 seconds, hold 5 seconds, then withdraw.
  4. 4Rotate sites each administration and dispose of the syringe in a sharps container.

Frequently Asked Questions

Third-party HPLC testing

CG Labz Verified Batches

No published batches yet.

Research Disclaimer

All compounds are supplied strictly for laboratory research. Dosing figures below summarize ranges reported in published preclinical and clinical literature for reference purposes only. CG Labz does not provide medical advice or individualized dosing recommendations.

Peer-reviewed literature

References

  1. [1] Journal of Endocrinology
    Tomas F.M. et al. Long-R3-IGF-1 and protein metabolism.
    View Source