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ToolsCompareThymulin vs HGH Fragment 176-191

Thymulin vs HGH Fragment 176-191

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

Immune Support
Thymulin
Fat Loss & Metabolic
HGH Fragment 176-191
Summary
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.
HGH Fragment 176-191 (also known as AOD-9604) is a stabilized, modified fragment of the human growth hormone molecule corresponding to amino acids 176–191 with an addition of a tyrosine residue at the N-terminus. It retains HGH's fat-burning properties without the anabolic, diabetogenic, or IGF-1-stimulating effects.
Half-Life
~30 minutes active half-life
~30 minutes
Admin Route
SubQ
SubQ
Research
Typical Dose
20-30 mcg
250–500 mcg
Frequency
10 days per month (Khavinson protocol)
1–3 times daily
Key Benefits
  • 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
  • Selective fat burning without anabolic side effects
  • Reduces visceral and subcutaneous fat
  • No insulin resistance or blood glucose disruption
  • Does not stimulate IGF-1
  • May support cartilage and bone repair (at higher doses)
  • No effect on growth or organ size
Side Effects
  • Injection site reactions
  • Mild fatigue initially as immune system activates
  • Injection site irritation
  • Temporary lethargy
  • Headache (rare)
  • Nausea (rare)
Stacks With