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ToolsCompareGonadorelin vs IGF-1 LR3

Gonadorelin vs IGF-1 LR3

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

Sexual Health & LibidoAnti-Aging & Longevity
Gonadorelin
Anabolic & IGF
IGF-1 LR3
Summary
Gonadorelin is the synthetic form of endogenous GnRH (gonadotropin-releasing hormone). It stimulates the pituitary to release LH and FSH, maintaining testicular function and testosterone production. Widely used alongside TRT to prevent testicular atrophy and preserve fertility.
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
~2–4 minutes (extremely short); pulsatile dosing required to avoid desensitization
20–30 hours
Admin Route
SubQ, Intranasal
SubQ, IM
Research
Typical Dose
100 mcg
40–80 mcg
Frequency
Twice daily (every 12 hours)
Once daily or split twice daily
Key Benefits
  • Maintains testicular size during TRT
  • Preserves fertility and sperm production during testosterone use
  • Stimulates endogenous LH/FSH production
  • Maintains HPG axis function during exogenous hormone use
  • Used for HCG-free TRT protocols
  • Helps restart natural testosterone production (PCT)
  • 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 reactions
  • Headache
  • Nausea at initiation
  • Tachycardia (rare)
  • +1 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