IGF-1 LR3
Long R3 Insulin-like Growth Factor-1
IGF-1 LR3 is a synthetic analog of human insulin-like growth factor 1, engineered with an arginine substitution at position 3 and 13 additional amino acids at the N-terminus. This 83-amino acid peptide exhibits reduced affinity for IGF-binding proteins, resulting in a prolonged half-life of 20-30 hours and approximately 3 times greater potency than native IGF-1. Currently investigational and not FDA-approved for human use.
IGF-1 LR3 Dosing Guide
Primary Benefits
- Enhanced muscle fiber hypertrophy and satellite cell activation
- Accelerated muscle recovery and protein synthesis
- Reduced muscle catabolism and improved nitrogen retention
- Enhanced glucose uptake and insulin sensitivity
- Promoted angiogenesis and vascular development
How It Works
IGF-1 LR3 binds to and activates the IGF-1 receptor (IGF-1R), a transmembrane tyrosine kinase receptor. Upon binding, IGF-1R undergoes autophosphorylation and activates downstream signaling cascades including the PI3K-Akt pathway (promoting protein synthesis and cell survival) and the MAPK pathway (stimulating cellular proliferation and differentiation). The key modification—arginine substitution at position 3 and 13 N-terminal amino acids—significantly reduces binding to IGF-binding proteins (IGFBPs), particularly IGFBP-3, resulting in increased bioavailability and extended half-life. This enhanced bioactivity allows for more sustained activation of anabolic pathways in target tissues, particularly skeletal muscle, where it stimulates satellite cell activation, myofibrillar protein synthesis, and muscle fiber hypertrophy.
Quick Reference
Typical Dosage Range
Research protocols typically employ 20-50 mcg daily via subcutaneous injection, administered as a single dose or divided into two doses (morning and post-workout). Starting protocols begin with 20-30 mcg daily for 7-14 days to assess tolerance, followed by potential increases of 10-20 mcg weekly up to 80-100 mcg maximum daily dose. Cycle length is standardized at 4-6 weeks active treatment followed by 3-6 weeks off-cycle to prevent receptor desensitization. Blood glucose monitoring is mandatory due to >40% hypoglycemia incidence. Injection sites should be rotated between abdomen, thighs, and upper arms to prevent tissue irritation.
Administration Methods
IGF-1 LR3 is administered via subcutaneous injection using insulin syringes (29-31 gauge, 0.5-1.0 mL capacity). Reconstitution requires bacteriostatic water or sterile saline at 1 mg/mL concentration under aseptic conditions. Injection sites should be rotated systematically between abdomen (2 inches from navel), anterior thigh, and posterior upper arm to prevent lipodystrophy. Timing is critical: administer on empty stomach (minimum 2-hour fast) or within 30 minutes post-workout for optimal receptor sensitivity. Storage requires refrigeration at 2-8°C after reconstitution, with stability maintained for 14 days maximum.
What It's Used For
IGF-1 LR3 is a synthetic analog of human insulin-like growth factor 1, engineered with an extended half-life of 20-30 hours and approximately 3 times greater potency than native IGF-1. This research compound is designed to enhance muscle growth, accelerate recovery, and improve metabolic function through sustained IGF-1 receptor activation.
Muscle Growth & Recovery
- Enhanced muscle fiber hypertrophy
- Accelerated protein synthesis
- Improved satellite cell activation
- Faster post-workout recovery
Metabolic Enhancement
- Enhanced glucose uptake
- Improved insulin sensitivity
- Increased fat metabolism
- Better nutrient partitioning
Tissue Regeneration
- Enhanced wound healing
- Improved bone mineral density
- Promoted angiogenesis
- Neuroprotective effects
How Much to Take
Beginner Protocol
20-30 mcg daily for 1-2 weeks to assess tolerance. Single subcutaneous injection, preferably morning or post-workout.
Standard Protocol
30-50 mcg daily for experienced users. Can be split into morning and post-workout doses for enhanced effect.
Advanced Protocol
50-80 mcg daily maximum. Requires careful blood glucose monitoring due to increased hypoglycemia risk.
Frequency
Once daily due to 20-30 hour half-life. Can split into two doses for enhanced muscle targeting.
Timing
Morning on empty stomach or within 30 minutes post-workout for optimal receptor sensitivity.
Adjustment
Increase by 10-20 mcg weekly if well-tolerated. Never exceed 80-100 mcg daily maximum.
How Long to Use It
Cycle Protocol
Standard research protocols employ 4-6 weeks active treatment followed by 3-6 weeks off-cycle to prevent receptor desensitization and maintain effectiveness.
The extended half-life of 20-30 hours means effects persist longer than native IGF-1, requiring adequate recovery periods between cycles.
Critical Safety Requirements
- Blood glucose monitoring mandatory - Over 40% of users experience hypoglycemia
- Never exceed 6-week cycles - Longer use increases receptor desensitization risk
- Research compound only - Not FDA-approved for human therapeutic use
- Medical supervision required - Serious side effects possible including seizures
Need-to-Know Information
How It Works
IGF-1 LR3 is like a supercharged version of your body's natural growth signal. It slips past the security guards (binding proteins) that normally grab and hide the key, staying active for 20-30 hours instead of just 12-15 hours. Once it unlocks muscle receptors, it triggers a construction crew inside your cells to build more protein, repair damage faster, and grow stronger muscle fibers.
Key Benefits
Muscle Growth
Animal studies show 20-40% muscle mass increases in just 2 weeks at research doses.
Enhanced Recovery
Accelerates healing of tissues after intense physical activity and promotes faster repair.
Extended Activity
20-30 hour half-life provides sustained anabolic effects compared to native IGF-1.
Who Should Avoid It
- Active malignancy or cancer history
- Uncontrolled diabetes or severe hypoglycemia risk
- Pregnancy or breastfeeding
- Severe cardiovascular disease
- Pediatric use without medical supervision
Possible Side Effects
- Hypoglycemia (42.5% of users)
- Injection site reactions (25.8%)
- Joint discomfort (18.3%)
- Water retention (15.7%)
- Headaches and fatigue (12.4%)
Storage & Injection
Storage Requirements
- Lyophilized: Store at -20°C
- Reconstituted: 2-8°C refrigeration
- Stability: Use within 14 days after mixing
- Protection: Keep away from light
Reconstitution
- Solution: Bacteriostatic water or sterile saline
- Concentration: 1 mg/mL standard
- Technique: Aseptic conditions required
- Mixing: Gentle swirling, no shaking
Injection Sites
Subcutaneous injection in abdomen (2 inches from navel), anterior thigh, or posterior upper arm. Rotate sites systematically.
Method
Use insulin syringes (29-31 gauge). Pinch skin fold, insert at 45-90° angle, inject slowly, hold for 5 seconds before withdrawing.
Safety Tips
Clean injection site with alcohol. Use new needle each time. Dispose of sharps properly. Monitor for reactions.
Example Schedule
4-Week Research Protocol
Week 1-2: Start Phase
20-30 mcg daily, morning injection on empty stomach. Monitor blood glucose closely.
Week 3-4: Maintenance
30-50 mcg daily if well-tolerated. Can split morning/post-workout if desired.
Week 5-8: Off Cycle
Complete break to prevent receptor desensitization and restore natural sensitivity.
Missed Dose Protocol
If you miss a dose by more than 12 hours, skip it and resume with your next scheduled dose. Due to the 20-30 hour half-life, doubling doses can increase hypoglycemia risk significantly. Never take two doses within 24 hours.
Extra Tips for Best Results
Optimization Tips
- Inject on empty stomach for maximum absorption
- Post-workout timing enhances muscle targeting
- Combine with high-protein diet (1.5-2g/kg)
- Maintain consistent injection schedule
Safety Monitoring
- Check blood glucose 2-3 times daily
- Keep glucose tablets or snacks handy
- Monitor injection sites for reactions
- Track progress and side effects daily
Lifestyle Support
- Maintain 7-9 hours quality sleep
- Stay well-hydrated throughout the day
- Follow structured resistance training
- Manage stress levels effectively
Expected Results Timeline
Week 1-2
Enhanced recovery, improved sleep quality, initial strength gains
Week 3-4
Visible muscle fullness, reduced body fat, faster workout recovery
Week 5-6
Peak anabolic effects, significant strength increases, body composition changes
Critical Warnings
- Research compound only - Not FDA-approved for human therapeutic use
- Medical supervision required - Serious hypoglycemic episodes possible
- Cancer risk - May accelerate tumor growth in susceptible individuals
- Blood glucose monitoring mandatory - Over 40% experience hypoglycemia
- Never exceed recommended doses - Higher doses dramatically increase risks
Medical Disclaimer
IGF-1 LR3 is an investigational research compound not approved by the FDA for human therapeutic use. This information is provided for educational purposes only and should not be construed as medical advice. IGF-1 LR3 carries significant risks including severe hypoglycemia and potential tumor growth acceleration. Any use should only occur under strict medical supervision in approved research settings. Individuals with cancer history, diabetes, or other serious medical conditions should not use this compound.