C-peptide vs Cosyntropin

Head-to-head comparison of C-peptide (Connecting peptide (C-peptide)) and Cosyntropin (Cosyntropin (ACTH 1-24)) — benefits, dosing, side effects, research data, and where to buy.

Research Score

PropertyC-peptideCosyntropin
CategoryPain ManagementPain Management
Full NameConnecting peptide (C-peptide)Cosyntropin (ACTH 1-24)
Molecular Weight3020.3 Da2933.3 Da
Half-Life~20-30 min~10 min
Amino Acids3124
Typical Doseno approved analgesic dose|research-only0.25 mg IV/IM diagnostic dose|off-label headache protocols vary
RouteIV|subQIV|IM
Purity≥98%≥98%
Studies Count4661
Research StatusPre-clinicalClinical research

C-peptide Benefits

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

Cosyntropin Benefits

  • refractory migraine
  • anti-inflammatory signaling
  • headache rescue research

C-peptide Dosing

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

Cosyntropin Dosing

0.25 mg IV/IM|1 mg IV/IM

C-peptide Side Effects

  • injection-site reactions
  • unknown long-term safety

Cosyntropin Side Effects

  • flushing
  • nausea

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.

Cosyntropin

Cosyntropin is not a standard pain drug, but it appears in headache literature because ACTH analogs can help some patients with difficult migraine attacks. The analgesic rationale is partly tied to steroidogenic and anti-inflammatory effects.

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Common Stacking Partners

C-peptide stacks with:

C-peptideConnecting peptide

Cosyntropin stacks with:

ACTH(1-24)Synacthen
neuropathic-paindiabetic-neuropathynerve-repairmigraineheadacheACTH-analog