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ToolsCompareMK-677 (Ibutamoren) vs Selank

MK-677 (Ibutamoren) vs Selank

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

Growth Hormone Peptides
MK-677 (Ibutamoren)
Cognitive Enhancement
Selank
Summary
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.
Selank is a synthetic heptapeptide analog of tuftsin developed in Russia. It is a potent anxiolytic that reduces anxiety and enhances cognitive function without sedation or addiction. It is approved for clinical use in Russia for anxiety disorders.
Half-Life
24 hours
Minutes (but effects persist for hours)
Admin Route
Oral
SubQ, Intranasal
Research
Typical Dose
10–25 mg
250–500 mcg
Frequency
Once daily
1–3 times daily
Key Benefits
  • 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
  • Reduces anxiety without sedation
  • Enhances memory and learning
  • Improves focus and concentration
  • Stabilizes mood
  • Reduces physiological stress response
  • May enhance motivation
  • No addiction potential or withdrawal
  • Fast-acting — effects within 20–30 minutes
  • Approved clinically in Russia for anxiety disorders
Side Effects
  • Increased appetite (significant in some users)
  • Water retention and puffiness
  • Elevated blood glucose / insulin resistance (monitor in diabetics)
  • Lethargy initially
  • +2 more
  • Mild sedation at higher doses (paradoxical)
  • Fatigue (rare)
  • Irritability during discontinuation (uncommon)
Stacks With