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ToolsCompareSermorelin vs Thymagen

Sermorelin vs Thymagen

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

Growth Hormone PeptidesAnti-Aging & Longevity
Sermorelin
Immune Support
Thymagen
Summary
Sermorelin is a bioidentical synthetic peptide comprising the first 29 amino acids of naturally occurring GHRH. It is FDA-approved for diagnostic use and widely prescribed off-label for anti-aging, stimulating growth hormone production in a natural pulsatile pattern that mimics the body's own rhythm.
Thymagen is a dipeptide bioregulator (Glu-Asp) developed by Professor Vladimir Khavinson, tissue-specific for the thymus gland. It supports T-lymphocyte maturation, thymic function, and immune system normalization. As the thymus involutes with age (thymic atrophy), immune competence declines. Thymagen is used to support immune restoration, particularly in aging, post-illness recovery, and immunodeficiency states.
Half-Life
10–20 minutes
Short (minutes); sustained gene-regulatory effects
Admin Route
SubQ
SubQ, Oral
Research
Typical Dose
200–500 mcg
10 mg per day
Frequency
5–7 days per week
Daily for 10–30 days
Key Benefits
  • Increases energy and vitality
  • Improves body composition (more muscle, less fat)
  • Enhances skin thickness and elasticity
  • Strengthens immune system
  • Improves sleep quality and REM sleep
  • Supports bone density
  • Enhances mental clarity and focus
  • Safer than exogenous HGH — respects natural feedback loops
  • FDA-approved for GH diagnostic use
  • Supports thymic epithelial cell function and T-cell maturation
  • May partially restore thymic output reduced by age-related atrophy
  • Normalizes T-lymphocyte subpopulation balance
  • Supports immune recovery after illness, surgery, or chemotherapy
  • Anti-aging effects on thymic tissue
  • Complementary to Thymosin Alpha-1 and Thymalin in immune protocols
  • May improve vaccine responsiveness in older individuals
Side Effects
  • Injection site irritation
  • Flushing
  • Headache
  • Dizziness
  • +2 more
  • Generally well tolerated
  • Mild injection site reactions
  • No significant immunological adverse events reported
Stacks With