MK-677 vs Capromorelin

Head-to-head comparison of MK-677 (Ibutamoren Mesylate (MK-677)) and Capromorelin (Capromorelin hydrochloride) — benefits, dosing, side effects, research data, and where to buy.

Research Score

PropertyMK-677Capromorelin
CategoryGrowth HormoneGrowth Hormone
Full NameIbutamoren Mesylate (MK-677)Capromorelin hydrochloride
Molecular Weight528.662 g/molN/A
Half-Life~24 hoursabout 2-3 hours
Amino AcidsNon-peptide compoundN/A
Typical Dose0.25-2 mg/kg/day
RouteOral
Purity>99%≥98%
Studies Count12055
Research StatusActive ResearchClinical

MK-677 Benefits

  • Oral GH secretagogue, 24-hour GH elevation, increases IGF-1, improves sleep quality, increases lean mass, does not suppress natural GH

Capromorelin Benefits

  • GH secretagogue activity
  • appetite stimulation
  • oral administration
  • translational animal model utility

MK-677 Dosing

10-25 mg orally once daily before bedtime. 25 mg is the most studied dose. Can be used long-term without cycling.

Capromorelin Dosing

0.25-2 mg/kg orally in studies|once-daily or protocol-specific dosing|monitor appetite and body weight

MK-677 Side Effects

  • Increased appetite, mild water retention, drowsiness, transient numbness, mild increase in fasting blood glucose with long-term use.

Capromorelin Side Effects

  • increased appetite
  • vomiting or nausea
  • lethargy

Research Overview

MK-677

A landmark 2-year study in elderly adults demonstrated significant increases in lean mass, GH pulsatility, and IGF-1 to youthful ranges. Selectively agonizes GHS-R1a without increasing cortisol or prolactin.

Capromorelin

Research consistently shows capromorelin activates the ghrelin receptor pathway and increases food intake. Human development has been less prominent than veterinary use, but the compound remains a relevant GH secretagogue prototype.

Ready to buy?

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Common Stacking Partners

MK-677 stacks with:

CJC-1295IpamorelinRAD-140

Capromorelin stacks with:

Nutritional supportResistance training
growth-hormone-secretagogueoralghrelin-mimeticIGF-1muscle-growthsleepghrelin-receptor-agonistappetite-stimulantgh-secretagogue