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ToolsCompareTB-500 vs MK-677 (Ibutamoren)

TB-500 vs MK-677 (Ibutamoren)

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

Recovery & Repair
TB-500
Growth Hormone Peptides
MK-677 (Ibutamoren)
Summary
TB-500 is a synthetic fragment of Thymosin Beta-4, a naturally occurring peptide found in nearly all human and animal cells. It promotes cell migration to injury sites, accelerates tissue regeneration, and reduces chronic inflammation.
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
2–3 hours
24 hours
Admin Route
SubQ, IM
Oral
Research
Typical Dose
2–2.5 mg
10–25 mg
Frequency
Twice weekly
Once daily
Key Benefits
  • Enhances muscle tissue regeneration
  • Accelerates healing of wounds and injuries
  • Reduces inflammation and pain
  • Improves flexibility and mobility
  • Promotes new blood vessel formation
  • Supports hair growth and skin health
  • May improve cardiac function after injury
  • Systemic healing effect — works at distance from injection site
  • 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 discomfort
  • Fatigue (rare)
  • Headache (rare)
  • Increased appetite (significant in some users)
  • Water retention and puffiness
  • Elevated blood glucose / insulin resistance (monitor in diabetics)
  • Lethargy initially
  • +2 more
Stacks With