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ToolsCompareIGF-1 LR3 vs Thymosin Beta-4

IGF-1 LR3 vs Thymosin Beta-4

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

Anabolic & IGF
IGF-1 LR3
Recovery & RepairAnti-Aging & Longevity
Thymosin Beta-4
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 Beta-4 is an endogenous 43-amino acid peptide that is the primary intracellular actin sequestering peptide. It promotes tissue repair, reduces inflammation, regenerates hair follicles, and protects cardiac tissue. Closely related to TB-500 (the active fragment), it is used for systemic tissue recovery and anti-aging.
Half-Life
20–30 hours
Not well characterized; likely similar to TB-500 (~1–2 hours)
Admin Route
SubQ, IM
SubQ, IM
Research
Typical Dose
40–80 mcg
5–10 mg
Frequency
Once daily or split twice daily
2x per week (loading), then 1x per week (maintenance)
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
  • Systemic tissue repair and regeneration
  • Promotes cardiac recovery after myocardial infarction
  • Hair follicle regeneration and anti-hair-loss
  • Anti-inflammatory (systemic)
  • Wound healing acceleration
  • Neuroprotection after brain injury
  • Protects against ischemia-reperfusion injury
  • Anti-aging at cellular level
  • Synergizes powerfully with BPC-157
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
  • Generally very well tolerated
  • Injection site reactions
  • Mild fatigue at initiation (repair signaling)
  • Rare: mild inflammatory response
  • +1 more
Stacks With