C-peptide vs Endomorphin-1

Head-to-head comparison of C-peptide (Connecting peptide (C-peptide)) and Endomorphin-1 (Tyr-Pro-Trp-Phe-NH2) — benefits, dosing, side effects, research data, and where to buy.

Research Score

PropertyC-peptideEndomorphin-1
CategoryPain ManagementPain Management
Full NameConnecting peptide (C-peptide)Tyr-Pro-Trp-Phe-NH2
Molecular Weight3020.3 Da610.71 Da
Half-Life~20-30 minMinutes in plasma
Amino Acids314
Typical Doseno approved analgesic dose|research-only0.1-10 ug per animal
RouteIV|subQIntrathecal / subcutaneous
Purity≥98%≥98%
Studies Count46600
Research StatusPre-clinicalPre-clinical

C-peptide Benefits

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

Endomorphin-1 Benefits

  • mu-opioid selectivity
  • potent antinociception
  • endogenous peptide scaffold
  • useful for receptor-discovery studies

C-peptide Dosing

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

Endomorphin-1 Dosing

Intrathecal 0.1-10 ug per animal|Subcutaneous 0.1-5 ug per animal|In vitro 0.1-100 nM

C-peptide Side Effects

  • injection-site reactions
  • unknown long-term safety

Endomorphin-1 Side Effects

  • respiratory depression at high exposure
  • sedation
  • tolerance and dependence potential

Research Overview

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.

Endomorphin-1

Endomorphin-1 is a key research peptide in studies of endogenous mu-opioid signaling and spinal analgesia. Like other peptide analgesics, its main translational hurdles are enzymatic instability, limited oral bioavailability, and delivery across barriers.

Ready to buy?

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Common Stacking Partners

C-peptide stacks with:

C-peptideConnecting peptide

Endomorphin-1 stacks with:

gabapentinketamine
neuropathic-paindiabetic-neuropathynerve-repairmu-opioidendogenous-peptideanalgesiapain-modulation