Orexin-A vs Macimorelin

Head-to-head comparison of Orexin-A (Hypocretin-1 (Orexin-A)) and Macimorelin (Macimorelin acetate (AEZS-130)) — benefits, dosing, side effects, research data, and where to buy.

Research Score

PropertyOrexin-AMacimorelin
CategoryCognitive EnhancementGrowth Hormone
Full NameHypocretin-1 (Orexin-A)Macimorelin acetate (AEZS-130)
Molecular Weight3562 DaN/A
Half-LifeMinutes to <1 hourabout 4-6 hours
Amino Acids33N/A
Typical DoseResearch-only; no validated human dose0.5 mg/kg single oral dose
RouteIntracerebroventricular/IntranasalOral
Purity≥98%≥98%
Studies Count42120
Research StatusPre-clinicalClinical

Orexin-A Benefits

  • wakefulness
  • attention
  • memory consolidation
  • fatigue resistance

Macimorelin Benefits

  • diagnostic GH stimulation
  • single oral dose
  • rapid measurable GH response
  • high clinical utility

Orexin-A Dosing

Research-only i.c.v. microgram/nanomolar studies|intranasal experimental use|no established human protocol

Macimorelin Dosing

0.5 mg/kg orally as a single dose|fasted testing conditions|serial GH sampling after administration

Orexin-A Side Effects

  • insomnia
  • headache
  • blood pressure changes

Macimorelin Side Effects

  • dysgeusia or taste disturbance
  • nausea
  • headache

Research Overview

Orexin-A

Preclinical studies link orexin signaling to arousal, learning, and memory consolidation, making orexin-A a candidate for cognition-related research. It is not an approved cognitive enhancer and remains an experimental peptide.

Macimorelin

Macimorelin has been validated in clinical testing as an oral alternative to injectable GH stimulation tests. Its short-term use makes it a useful translational tool for evaluating pituitary GH reserve.

Ready to buy?

Find both peptides from our verified, lab-tested vendors with purity certificates and third-party testing.

Common Stacking Partners

Orexin-A stacks with:

PRL-8-53Bromantane

Macimorelin stacks with:

Pituitary testingEndocrine workup
peptidewakefulnessmemorydiagnosticghrelin-mimeticgh-stimulation-test