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ToolsCompareIGF-1 LR3 vs Thymosin Alpha-1

IGF-1 LR3 vs Thymosin Alpha-1

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

Anabolic & IGF
IGF-1 LR3
Immune SupportAnti-Aging & Longevity
Thymosin Alpha-1
Summary
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.
Thymosin Alpha-1 is a naturally occurring 28-amino acid peptide derived from the thymus gland. It is a powerful immune modulator approved in many countries for treating chronic hepatitis B, hepatitis C, and as an adjunct in cancer immunotherapy.
Half-Life
20–30 hours
2–3 hours
Admin Route
SubQ, IM
SubQ
Research
Typical Dose
40–80 mcg
0.8–1.6 mg
Frequency
Once daily or split twice daily
Twice weekly
Key Benefits
  • 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
  • Enhances T-cell and NK cell activity
  • Supports recovery from viral and bacterial infections
  • May reduce inflammation systemically
  • Supports healthy aging and immune resilience
  • Improves vaccine response
  • Supports liver health
  • May help with chronic fatigue syndrome and post-viral conditions
  • Approved in multiple countries for hepatitis B and C treatment
Side Effects
  • 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
  • Injection site irritation
  • Mild flu-like symptoms initially (immune activation)
  • Fatigue (rare)
Stacks With