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ToolsCompareThymalin vs Somatropin (HGH)

Thymalin vs Somatropin (HGH)

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

Immune SupportAnti-Aging & Longevity
Thymalin
Growth Hormone PeptidesAnti-Aging & Longevity
Somatropin (HGH)
Summary
Thymalin is a polypeptide complex isolated from calf thymus glands (developed by the Russian Gerontology Institute), shown to restore immune function, extend lifespan, and reverse thymic involution. Clinical studies demonstrate improved immune parameters and up to 40% reduction in mortality in elderly patients.
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.
Half-Life
Not well characterized as a complex extract; individual peptides have varying kinetics
2-3 hours (subcutaneous); 20-30 minutes (intravenous)
Admin Route
SubQ, IM
Subcutaneous, Intramuscular (less common)
Research
Typical Dose
10 mg IM or SC daily
0.15-0.3 mg/day (adults); titrated to IGF-1 levels
Frequency
Once daily
Once daily
Key Benefits
  • Restores thymic function and T-cell immunity
  • Extends healthy lifespan (documented in long-term studies)
  • Reduces infectious disease incidence in elderly
  • Normalizes immune parameters in immunodeficiency
  • Anti-tumor immune surveillance
  • Improves vaccine response in elderly
  • Reduces cardiovascular mortality (40% in landmark Russian study)
  • Normalizes neuroendocrine function
  • 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
Side Effects
  • Very well tolerated in decades of Russian clinical use
  • Mild injection site reactions
  • Rare: mild allergic reaction (natural extract)
  • Transient flu-like symptoms on initiation (immune activation)
  • Fluid retention and edema (common, dose-dependent)
  • Carpal tunnel syndrome
  • Joint and muscle pain
  • Insulin resistance and elevated blood glucose
  • +3 more
Stacks With