C-peptide vs Kisspeptin-54

Head-to-head comparison of C-peptide (Connecting peptide (C-peptide)) and Kisspeptin-54 (Kisspeptin-54 (metastin), 54-amino-acid KISS1 peptide fragment) — benefits, dosing, side effects, research data, and where to buy.

Research Score

PropertyC-peptideKisspeptin-54
CategoryPain ManagementSexual Health
Full NameConnecting peptide (C-peptide)Kisspeptin-54 (metastin), 54-amino-acid KISS1 peptide fragment
Molecular Weight3020.3 Da5.9 kDa
Half-Life~20-30 minabout 20-30 min
Amino Acids3154
Typical Doseno approved analgesic dose|research-only0.3-1.0 nmol/kg
RouteIV|subQIntravenous
Purity≥98%≥98%
Studies Count46110
Research StatusPre-clinicalClinical

C-peptide Benefits

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

Kisspeptin-54 Benefits

  • GnRH/LH stimulation
  • supports sex hormone signaling
  • may enhance sexual motivation
  • fertility-axis modulation

C-peptide Dosing

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

Kisspeptin-54 Dosing

0.3-1.0 nmol/kg IV bolus|single-dose experimental protocols|research-only endocrine monitoring

C-peptide Side Effects

  • injection-site reactions
  • unknown long-term safety

Kisspeptin-54 Side Effects

  • flushing
  • nausea
  • headache
  • hormonal shifts

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.

Kisspeptin-54

Human studies show that kisspeptin-54 can acutely modulate reproductive neuroendocrine signaling, which makes it relevant to libido and sexual motivation research. Its effects are indirect compared with PT-141, but it is a well-established peptide in the scientific literature.

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Common Stacking Partners

C-peptide stacks with:

C-peptideConnecting peptide

Kisspeptin-54 stacks with:

BremelanotideAlpha-MSH
neuropathic-paindiabetic-neuropathynerve-repairreproductive-axislibidoendocrineresearch-peptide