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ToolsCompareThymalin vs Tesamorelin

Thymalin vs Tesamorelin

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

Immune SupportAnti-Aging & Longevity
Thymalin
Growth Hormone PeptidesFat Loss & Metabolic
Tesamorelin
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.
Tesamorelin is an FDA-approved synthetic GHRH analog specifically indicated for reduction of excess abdominal (visceral) fat in HIV patients with lipodystrophy. It is the only GHRH peptide with FDA approval for a fat-reduction indication and is studied off-label for metabolic syndrome and cognitive function.
Half-Life
Not well characterized as a complex extract; individual peptides have varying kinetics
~26 minutes
Admin Route
SubQ, IM
SubQ
Research
Typical Dose
10 mg IM or SC daily
2 mg
Frequency
Once daily
Once 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
  • FDA-approved for visceral fat reduction in HIV lipodystrophy
  • Significant reduction in trunk/visceral fat (average 15–20% in trials)
  • Improved triglyceride and lipid profiles
  • Potential cognitive benefits and memory improvement
  • Preserves lean mass while reducing fat
  • Natural pulsatile GH stimulation
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)
  • Injection site reactions (redness, irritation)
  • Arthralgia and joint pain
  • Peripheral edema
  • Carpal tunnel syndrome
  • +2 more
Stacks With