Sermorelin vs Thymulin
Side-by-side comparison of key properties, dosing, and research.
Growth Hormone PeptidesAnti-Aging & Longevity
SermorelinImmune Support
Thymulin- 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.
- 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
- 10–20 minutes
- ~30 minutes active half-life
- Admin Route
- SubQ
- SubQ
- Research
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- Typical Dose
- 200–500 mcg
- 20-30 mcg
- Frequency
- 5–7 days per week
- 10 days per month (Khavinson protocol)
- 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
- 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
- Injection site irritation
- Flushing
- Headache
- Dizziness
- +2 more
- Injection site reactions
- Mild fatigue initially as immune system activates
- Stacks With
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