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ToolsCompareThymalin vs GHRP-6

Thymalin vs GHRP-6

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

Immune SupportAnti-Aging & Longevity
Thymalin
Growth Hormone Peptides
GHRP-6
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.
GHRP-6 is the original synthetic GH-releasing peptide and a potent ghrelin receptor agonist. It produces strong GH pulses but is notorious for a significant hunger surge 30–45 minutes post-injection. This hunger side effect makes it less preferred than Ipamorelin or GHRP-2 for most protocols but can be useful in patients with appetite deficiency.
Half-Life
Not well characterized as a complex extract; individual peptides have varying kinetics
15–60 minutes
Admin Route
SubQ, IM
SubQ, Intranasal
Research
Typical Dose
10 mg IM or SC daily
100–300 mcg
Frequency
Once daily
2–3 times 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
  • Strong GH stimulation
  • Elevated IGF-1
  • Muscle growth and recovery support
  • Potential anti-inflammatory effects at GI level
  • Useful for patients with appetite deficiency or cachexia
  • Enhanced recovery from training
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)
  • Intense hunger surge (30–45 min post-injection)
  • Water retention
  • Elevated cortisol (modest)
  • Elevated prolactin (modest)
  • +2 more
Stacks With