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ToolsCompareHGH Fragment 176-191 vs Thymalin

HGH Fragment 176-191 vs Thymalin

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

Fat Loss & Metabolic
HGH Fragment 176-191
Immune SupportAnti-Aging & Longevity
Thymalin
Summary
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.
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.
Half-Life
~30 minutes
Not well characterized as a complex extract; individual peptides have varying kinetics
Admin Route
SubQ
SubQ, IM
Research
Typical Dose
250–500 mcg
10 mg IM or SC daily
Frequency
1–3 times daily
Once daily
Key Benefits
  • 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
  • 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
Side Effects
  • Injection site irritation
  • Temporary lethargy
  • Headache (rare)
  • Nausea (rare)
  • 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)
Stacks With