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ToolsCompareThymalin vs Pal-GHK

Thymalin vs Pal-GHK

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

Immune SupportAnti-Aging & Longevity
Thymalin
Skin & CosmeticAnti-Aging & Longevity
Pal-GHK
Summary
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.
Pal-GHK is the palmitoylated form of the GHK tripeptide without a copper ion. By conjugating palmitic acid to glycine-histidine-lysine, skin penetration is substantially enhanced, enabling deeper dermal collagen stimulation. It is commonly paired with Pal-GHK-Cu or GHK-Cu in anti-aging formulations.
Half-Life
Not well characterized as a complex extract; individual peptides have varying kinetics
Extended (lipid depot in stratum corneum)
Admin Route
SubQ, IM
Topical
Research
Typical Dose
10 mg IM or SC daily
0.005–0.1% in formulation
Frequency
Once daily
Once or twice daily
Key Benefits
  • 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
  • Stimulates collagen I and III synthesis in dermis
  • Reduces the appearance of fine lines and wrinkles
  • Improves skin elasticity and firmness
  • Inhibits collagenase (MMP-1) to preserve existing collagen
  • Enhances wound healing and skin repair
  • Well-tolerated in anti-aging serums and creams
Side Effects
  • 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)
  • Generally very well-tolerated
  • Rare skin irritation at very high concentrations
  • Possible formulation-dependent comedogenicity
Stacks With