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IGF-1 LR3

limited

Modified Growth Factor Analog | Muscle Growth

Dose 20-100 mcg daily (start low at 20-30 mcg)
Frequency Once daily, or split AM/PM for higher doses
Cycle 4-6 weeks maximum
Storage Lyophilized: -20°C to -80°C. Reconstituted in acetic acid: 2-8°C for 1 year. Reconstituted in BAC water: use within 7 days
Accumulation Plotter

IGF-1 LR3 is a synthetic 83-amino acid analog of insulin-like growth factor-1 that has never been approved for human use. The N-terminal extension and R3 substitution reduce binding protein interaction, maintaining elevated free circulating levels with ~3x greater potency than native IGF-1.

Mechanism of Action

Functions as a full IGF-1 receptor agonist activating PI3K/Akt/mTOR and MAPK/ERK pathways. The modifications prevent protein sequestration, maintaining elevated free circulating levels for extended anabolic effects.

Key Benefits

  • Approximately 3x more potent than native IGF-1
  • Promotes muscle hypertrophy and hyperplasia in animal models
  • 15-20% lean mass gains observed in 4-week rat studies
  • Anti-catabolic effects preserve muscle during cachexia
  • 20-30 hour half-life for sustained effects
Chain Length
83 amino acids
Type
Synthetic IGF-1 analog

Muscle Growth

  • Hypertrophy

    15-20% lean mass gains in 4 weeks through satellite cell activation (rat studies).

  • Anti-Catabolic

    Cancer cachexia rats maintained 30% more muscle versus placebo.

  • Hyperplasia

    Creates new muscle fibers via satellite cell differentiation.

Tissue Repair

  • Wound Healing

    Accelerated wound healing in animal models.

  • Ligament/Tendon Recovery

    Enhanced connective tissue repair.

Metabolic

  • Nutrient Partitioning

    Directs nutrients toward muscle tissue.

  • Fat Loss

    Enhanced lipolysis through IGF-1 pathway.

Subcutaneous or intramuscular injection. CRITICAL: Consume 30-60g fast carbohydrates immediately after injection to prevent hypoglycemia. Never inject before sleep.

GoalDoseFrequencyRoute
Beginner Protocol20-30mcgOnce daily post-workoutSubQ/IM
Intermediate40-60mcgOnce dailySubQ/IM
Advanced80-100mcgOnce or split AM/PMSubQ/IM
Women's Protocol10-20mcgOnce dailySubQ/IM

Reconstitution Instructions

Materials Needed:
  • IGF-1 LR3 lyophilized powder
  • 0.6% acetic acid OR bacteriostatic water
  • Insulin syringes (29-32 gauge)
  • Alcohol swabs
  1. 1 Equilibrate to room temperature (15-30 min)
  2. 2 Sanitize rubber stopper with alcohol
  3. 3 Calculate concentration (e.g., 1mg in 2mL = 500mcg/mL)
  4. 4 Inject diluent slowly along vial wall
  5. 5 Gently swirl - never shake vigorously
  6. 6 Allow 2-5 minutes for complete dissolution
  7. 7 Store immediately at 2-8°C protected from light
  8. 8 Acetic acid reconstitution: stable 1 year
  9. 9 BAC water reconstitution: use within 7 days
Human Growth Hormone

Creates excessive IGF-1 levels; avoid combination.

avoid
CJC-1295/Ipamorelin

Both stimulate GH/IGF-1 axis; use caution with combination.

monitor
MK-677

May compound metabolic effects through GH stimulation.

monitor
Insulin

Synergistic hypoglycemic effects can be life-threatening.

avoid
BPC-157

Complementary healing mechanisms.

synergistic
TB-500

Different repair pathway activation.

synergistic
Anabolic Steroids

Amplified effects with increased risks.

monitor
Metformin

May mitigate insulin resistance.

monitor
Cerebrolysin

Additive neurotrophic pathway effects.

monitor
Week 1-2

Increased muscle pump and fullness; possible hypoglycemia if carbs inadequate

Week 2-4

Enhanced recovery, strength gains, visible fullness, potential water retention

Week 4-6

Maximum effects; receptor desensitization approaching; joint stiffness common

Post-cycle

Pump loss over 1-2 weeks; strength/size gains may persist with training

Common Side Effects

  • Hypoglycemia (lasting up to 30 hours) - CRITICAL
  • Water retention
  • Joint stiffness
  • Muscle soreness
  • Increased pump during workouts

Stop Signs - Discontinue if:

  • Severe or recurring hypoglycemia despite carbohydrate intake
  • Unusual growths, lumps, or rapid mole changes
  • Severe joint pain or carpal tunnel symptoms
  • Persistent nausea, headaches, or vision changes
  • Signs of organ enlargement
  • Extreme fatigue or mental fog

Contraindications

  • NEVER approved for human use - research chemical only
  • Cancer history or undiagnosed growths
  • May cause organ hypertrophy (heart, intestines)
  • WADA prohibited - causes failed drug tests

Good Signs

  • HPLC purity >95%
  • Mass spectrometry confirmation
  • Cold storage maintained (-20°C lyophilized)
  • Certificate of analysis from reputable source

Warning Signs

  • Research chemical status - never approved for human use
  • Zero human clinical trials exist
  • Species-specific responses vary significantly

Bad Signs

  • Severe hypoglycemia risk - life-threatening low blood sugar lasting 20-30 hours
  • Cancer proliferation concern - UK Biobank links elevated IGF-1 to multiple cancers
  • Black market quality varies - oxidized and degraded forms common
  • Rat Muscle Hypertrophy Study - Florini et al.
    (1996)

    2.5mg/kg/day for 4 weeks showed 2.5x greater anabolic response compared to native IGF-1. Satellite cell activation and protein synthesis increased 50%.

  • Fetal Sheep Metabolic Study
    (2000)

    Acute infusion suppressed insulin secretion by 66%. Study halted early due to 4 animal deaths from hypoglycemia.

  • Cancer Cachexia Rat Model
    (1998)

    0.3mg/kg/day for 14 days showed 30% lean mass preservation during cachexia.

  • UK Biobank Cancer Association
    (2023)

    Elevated IGF-1 associated with multiple cancers including thyroid, colorectal, breast, prostate, melanoma.

Disclaimer

This information is for educational and research purposes only. Consult a healthcare professional before use.