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ToolsCompareSermorelin vs IGF-1 LR3

Sermorelin vs IGF-1 LR3

Side-by-side comparison of key properties, dosing, and research.

Growth Hormone PeptidesAnti-Aging & Longevity
Sermorelin
Anabolic & IGF
IGF-1 LR3
Summary
Sermorelin is a bioidentical synthetic peptide comprising the first 29 amino acids of naturally occurring GHRH. It is FDA-approved for diagnostic use and widely prescribed off-label for anti-aging, stimulating growth hormone production in a natural pulsatile pattern that mimics the body's own rhythm.
IGF-1 LR3 is a synthetic analog of Insulin-like Growth Factor-1 with an extended half-life. It is one of the most potent anabolic peptides available, directly stimulating muscle cell hyperplasia and hypertrophy, and is the downstream mediator of many of GH's anabolic effects.
Half-Life
10–20 minutes
20–30 hours
Admin Route
SubQ
SubQ, IM
Research
Typical Dose
200–500 mcg
40–80 mcg
Frequency
5–7 days per week
Once daily or split twice daily
Key Benefits
  • Increases energy and vitality
  • Improves body composition (more muscle, less fat)
  • Enhances skin thickness and elasticity
  • Strengthens immune system
  • Improves sleep quality and REM sleep
  • Supports bone density
  • Enhances mental clarity and focus
  • Safer than exogenous HGH — respects natural feedback loops
  • FDA-approved for GH diagnostic use
  • Direct muscle hypertrophy via IGF-1R stimulation
  • Muscle hyperplasia (new fiber formation) — unique among peptides
  • Rapid gains in lean muscle mass
  • Accelerated recovery from training and injury
  • Increased nutrient uptake by muscle cells
  • Fat oxidation enhancement
  • Bone density improvement
  • Cartilage and connective tissue repair
Side Effects
  • Injection site irritation
  • Flushing
  • Headache
  • Dizziness
  • +2 more
  • Hypoglycemia (significant risk — insulin-like activity)
  • Acromegaly-like effects with excessive long-term use
  • Jaw and hand swelling
  • Organ hypertrophy with extreme doses
  • +2 more
Stacks With