Side-by-Side Comparison · 2026

Dynorphin vs Enkephalin

Dynorphin vs Enkephalin — mechanism, half-life, dosing, and research status compared. Which is right for your protocol?

Dynorphin
Endogenous Opioid / Neuropeptide

Dynorphin is the principal endogenous agonist of kappa opioid receptors (KOR), encoded by the prodynorphin gene alongside alpha-neoendorphin, dynorphin B, and the leumorphin peptide. Unlike the rewarding and analgesic effects of mu opioid receptor (MOR) activation by endorphins a...

Calculate Dynorphin dose →
Enkephalin
Endogenous Opioid / Neuropeptide

Enkephalins are the shortest endogenous opioid peptides, pentapeptides encoded by the proenkephalin (PENK) gene, existing as two primary forms -- Met-enkephalin and Leu-enkephalin -- differing only at the C-terminal residue. As the principal endogenous ligands of delta opioid rec...

Calculate Enkephalin dose →
Key Parameters
Parameter Dynorphin Enkephalin
Category Endogenous Opioid / Neuropeptide Endogenous Opioid / Neuropeptide
Research Research / Endogenous Neuropeptide Research / Endogenous Neuropeptide
Half-Life 1-3 minutes (plasma) Seconds to minutes (rapidly cleaved by enkephalinases)
Typical Dose Research: 1-10 nmol ICV; intrathecal 0.5-5 nmol (rodent) Research: 1-10 nmol intrathecal; ICV 1-20 nmol (rodent)
Frequency Endogenous: stress/pain-activated release Endogenous: on neural depolarization; research per session
Route Endogenous (striatum, hypothalamus, spinal cord); research intrathecal/ICV Endogenous (brain, spinal cord, adrenal medulla, gut); research IV/intrathecal
FDA Status Not approved; KOR antagonists in clinical trials Not approved as agonist; enkephalinase inhibitors in research

Calculate doses for both

Use ASCEND's free reconstitution calculator to get exact syringe draw amounts for your vial.

Calculate Dynorphin Calculate Enkephalin
Frequently Asked Questions
What is the difference between Dynorphin and Enkephalin?
Dynorphin: Dynorphin is the principal endogenous agonist of kappa opioid receptors (KOR), encoded by the prodynorphin gene alongside alpha-neoendorphin, dynorphin B, and the leumorphin peptide. Unlike the reward... Enkephalin: Enkephalins are the shortest endogenous opioid peptides, pentapeptides encoded by the proenkephalin (PENK) gene, existing as two primary forms -- Met-enkephalin and Leu-enkephalin -- differing only at...
Which has a longer half-life, Dynorphin or Enkephalin?
Dynorphin half-life: 1-3 minutes (plasma). Enkephalin half-life: Seconds to minutes (rapidly cleaved by enkephalinases).
Can you stack Dynorphin and Enkephalin?
Dynorphin and Enkephalin are in the same category and used together in research protocols. Always consult relevant literature and follow appropriate guidelines.

For research use only. Not medical advice. ASCEND does not conduct or endorse any specific research protocol. Always consult relevant scientific literature and regulatory guidelines.