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ToolsCompareSomatropin (HGH) vs Thymosin Alpha-1

Somatropin (HGH) vs Thymosin Alpha-1

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

Growth Hormone PeptidesAnti-Aging & Longevity
Somatropin (HGH)
Immune SupportAnti-Aging & Longevity
Thymosin Alpha-1
Summary
Somatropin is recombinant human growth hormone (rhGH), identical in structure to the 191-amino acid pituitary-derived growth hormone. It is FDA-approved for growth hormone deficiency, short stature, and wasting conditions. Off-label, it is widely explored for body composition, anti-aging, and performance enhancement, though significant risks accompany unsupervised use.
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
2-3 hours (subcutaneous); 20-30 minutes (intravenous)
2–3 hours
Admin Route
Subcutaneous, Intramuscular (less common)
SubQ
Research
Typical Dose
0.15-0.3 mg/day (adults); titrated to IGF-1 levels
0.8–1.6 mg
Frequency
Once daily
Twice weekly
Key Benefits
  • Increases lean muscle mass and reduces body fat (particularly visceral)
  • Restores growth hormone deficiency (FDA-approved)
  • Improves bone mineral density
  • Enhances exercise capacity and recovery
  • Supports skin thickness and collagen synthesis
  • Improves lipid profile in GHD patients
  • Explored for anti-aging and cellular regeneration
  • 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
  • Fluid retention and edema (common, dose-dependent)
  • Carpal tunnel syndrome
  • Joint and muscle pain
  • Insulin resistance and elevated blood glucose
  • +3 more
  • Injection site irritation
  • Mild flu-like symptoms initially (immune activation)
  • Fatigue (rare)
Stacks With