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ToolsCompareSomatropin (HGH) vs Thymulin

Somatropin (HGH) vs Thymulin

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

Growth Hormone PeptidesAnti-Aging & Longevity
Somatropin (HGH)
Immune Support
Thymulin
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.
Thymulin is a nonapeptide hormone produced exclusively by the thymic epithelium. It requires zinc for biological activity and plays a critical role in T-lymphocyte maturation, differentiation, and immune regulation. Thymulin levels decline dramatically with age, contributing to immunosenescence.
Half-Life
2-3 hours (subcutaneous); 20-30 minutes (intravenous)
~30 minutes active half-life
Admin Route
Subcutaneous, Intramuscular (less common)
SubQ
Research
Typical Dose
0.15-0.3 mg/day (adults); titrated to IGF-1 levels
20-30 mcg
Frequency
Once daily
10 days per month (Khavinson protocol)
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 maturation and differentiation
  • Boosts NK cell cytotoxic activity
  • Reduces inflammatory cytokine production (TNF-α, IL-1)
  • Anti-nociceptive (pain-reducing) properties
  • Restores age-related immune decline
  • Anti-inflammatory via serotonin pathway modulation
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 reactions
  • Mild fatigue initially as immune system activates
Stacks With