Cosyntropin vs Leu-enkephalin

Head-to-head comparison of Cosyntropin (Cosyntropin (ACTH 1-24)) and Leu-enkephalin (Tyr-Gly-Gly-Phe-Leu) — benefits, dosing, side effects, research data, and where to buy.

Research Score

PropertyCosyntropinLeu-enkephalin
CategoryPain ManagementPain Management
Full NameCosyntropin (ACTH 1-24)Tyr-Gly-Gly-Phe-Leu
Molecular Weight2933.3 Da555.63 Da
Half-Life~10 min1-5 minutes in plasma
Amino Acids245
Typical Dose0.25 mg IV/IM diagnostic dose|off-label headache protocols vary0.1-5 ug per animal
RouteIV|IMIntrathecal / intracerebroventricular
Purity≥98%≥98%
Studies Count611000
Research StatusClinical researchPre-clinical

Cosyntropin Benefits

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

Leu-enkephalin Benefits

  • delta-opioid activity
  • endogenous analgesic model
  • receptor-selective pharmacology
  • nociception pathway research

Cosyntropin Dosing

0.25 mg IV/IM|1 mg IV/IM

Leu-enkephalin Dosing

Intrathecal 0.1-5 ug per animal|Intracerebroventricular 0.1-2 ug per animal|In vitro 1-100 nM

Cosyntropin Side Effects

  • flushing
  • nausea

Leu-enkephalin Side Effects

  • sedation
  • constipation-like opioid effects
  • very short plasma stability

Research Overview

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.

Leu-enkephalin

Leu-enkephalin is a standard tool in opioid receptor and pain-transmission research because it helps distinguish delta- from mu-preferring signaling. Its research value is high, but its clinical utility is limited by rapid enzymatic breakdown and delivery challenges.

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Common Stacking Partners

Cosyntropin stacks with:

ACTH(1-24)Synacthen

Leu-enkephalin stacks with:

gabapentinketamine
migraineheadacheACTH-analogopioid-peptideenkephalindelta-opioidanalgesia