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ToolsCompareGHRP-6 vs Thymulin

GHRP-6 vs Thymulin

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

Growth Hormone Peptides
GHRP-6
Immune Support
Thymulin
Summary
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.
Thymulin is a nonapeptide hormone produced exclusively by the thymic epithelium. It requires zinc for biological activity and plays a critical role in T-lymphocyte maturation, differentiation, and immune regulation. Thymulin levels decline dramatically with age, contributing to immunosenescence.
Half-Life
15–60 minutes
~30 minutes active half-life
Admin Route
SubQ, Intranasal
SubQ
Research
Typical Dose
100–300 mcg
20-30 mcg
Frequency
2–3 times daily
10 days per month (Khavinson protocol)
Key Benefits
  • 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
  • Enhances T-cell maturation and differentiation
  • Boosts NK cell cytotoxic activity
  • Reduces inflammatory cytokine production (TNF-α, IL-1)
  • Anti-nociceptive (pain-reducing) properties
  • Restores age-related immune decline
  • Anti-inflammatory via serotonin pathway modulation
Side Effects
  • Intense hunger surge (30–45 min post-injection)
  • Water retention
  • Elevated cortisol (modest)
  • Elevated prolactin (modest)
  • +2 more
  • Injection site reactions
  • Mild fatigue initially as immune system activates
Stacks With