MK-677 vs C-peptide

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

Research Score

PropertyMK-677C-peptide
CategoryGrowth HormonePain Management
Full NameIbutamoren Mesylate (MK-677)Connecting peptide (C-peptide)
Molecular Weight528.662 g/mol3020.3 Da
Half-Life~24 hours~20-30 min
Amino AcidsNon-peptide compound31
Typical Doseno approved analgesic dose|research-only
RouteIV|subQ
Purity>99%≥98%
Studies Count12046
Research StatusActive ResearchPre-clinical

MK-677 Benefits

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

C-peptide Benefits

  • diabetic neuropathy research
  • nerve function support
  • possible analgesic effect

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.

C-peptide Dosing

0.5-1.0 mg/day in research|route varies by protocol

MK-677 Side Effects

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

C-peptide Side Effects

  • injection-site reactions
  • unknown long-term safety

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.

C-peptide

C-peptide is not an approved analgesic, but multiple studies have examined its effects on peripheral nerve blood flow and neuropathy outcomes. The strongest relevance is in diabetic neuropathic pain rather than migraine.

Ready to buy?

Find both peptides from our verified, lab-tested vendors with purity certificates and third-party testing.

Common Stacking Partners

MK-677 stacks with:

CJC-1295IpamorelinRAD-140

C-peptide stacks with:

C-peptideConnecting peptide
growth-hormone-secretagogueoralghrelin-mimeticIGF-1muscle-growthsleepneuropathic-paindiabetic-neuropathynerve-repair