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ToolsCompareLL-37 vs MK-677 (Ibutamoren)

LL-37 vs MK-677 (Ibutamoren)

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

Immune SupportRecovery & Repair
LL-37
Growth Hormone Peptides
MK-677 (Ibutamoren)
Summary
LL-37 is the only known human cathelicidin antimicrobial peptide. It kills bacteria, fungi, and viruses by disrupting their membranes, while simultaneously modulating immune responses. Used for antimicrobial protection, immune priming, and wound healing.
MK-677 (Ibutamoren) is an orally active, non-peptide ghrelin receptor agonist that increases growth hormone and IGF-1 levels. Unlike injectable GHRPs, it can be taken orally and has a 24-hour half-life, making it convenient for sustained GH optimization.
Half-Life
Very short (~1–2 hours) in plasma due to protease degradation; topical use bypasses systemic clearance
24 hours
Admin Route
SubQ, Topical, Intranasal
Oral
Research
Typical Dose
100–300 mcg
10–25 mg
Frequency
2–3x per week
Once daily
Key Benefits
  • Broad-spectrum antimicrobial (bacteria, fungi, viruses)
  • Promotes wound healing and angiogenesis
  • Immune system modulation — enhances innate immunity
  • Reduces LPS-mediated endotoxemia
  • Anti-biofilm activity against resistant organisms
  • Promotes tissue regeneration and keratinocyte migration
  • May protect against sepsis
  • Increases lean muscle mass
  • Enhances bone density
  • Improves sleep quality and REM sleep
  • Accelerates recovery from training
  • Increases appetite
  • May improve skin elasticity and appearance
  • Supports fat loss while maintaining muscle
  • Oral administration — no injections required
  • 24-hour half-life allows once-daily dosing
Side Effects
  • Injection site redness and irritation
  • Mild inflammatory response at injection site
  • Potential pro-inflammatory at high doses
  • Rare: fever or flu-like symptoms at initiation
  • Increased appetite (significant in some users)
  • Water retention and puffiness
  • Elevated blood glucose / insulin resistance (monitor in diabetics)
  • Lethargy initially
  • +2 more
Stacks With