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ToolsCompareIpamorelin vs Thymalin

Ipamorelin vs Thymalin

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

Growth Hormone Peptides
Ipamorelin
Immune SupportAnti-Aging & Longevity
Thymalin
Summary
Ipamorelin is a selective GHRP (growth hormone releasing peptide) and one of the cleanest GH secretagogues available. It selectively stimulates GH release without significantly raising cortisol, prolactin, or appetite — making it ideal for long-term use and anti-aging protocols.
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
2 hours
Not well characterized as a complex extract; individual peptides have varying kinetics
Admin Route
SubQ
SubQ, IM
Research
Typical Dose
100–300 mcg
10 mg IM or SC daily
Frequency
Once to twice daily
Once daily
Key Benefits
  • Increases lean muscle mass
  • Enhances fat loss
  • Improves recovery time
  • Strengthens bones and joints
  • Better sleep quality and REM sleep
  • Enhanced skin elasticity
  • Minimal impact on hunger or cortisol
  • No cortisol or prolactin spike
  • Clean GH release suitable for long-term protocols
  • 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 water retention (mild)
  • Possible hunger increase (milder than GHRP-6)
  • Numbness or tingling in extremities (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