GHRP-6 vs Melanotan II

Side-by-side comparison of mechanisms, dosing, interactions, and stacking potential.

GHRP-6Melanotan II
CategoryPeptidesPeptides
Standard DoseResearch indicates 100-300 mcg administered 1-3 times daily via subcutaneous injection.Research indicates 250-500 mcg daily via subcutaneous injection during loading, reducing to 250 mcg 2-3 times weekly for maintenance.
TimingOn empty stomach, 30+ minutes before meals. Bedtime dose most important. The strong hunger effect makes pre-meal timing practical.Administer 4-6 hours before UV exposure for optimal tanning synergy. Can be taken at any time of day.
Cycle Duration8-16 week cycles.Loading phase 1-2 weeks, then maintenance as long as desired. Pigmentation fades gradually upon discontinuation.
Evidence Levelmoderate_humanmoderate_human
A

GHRP-6

Peptides

Mechanism

GHRP-6 (Growth Hormone Releasing Peptide-6) is a synthetic hexapeptide that stimulates GH release through activation of the growth hormone secretagogue receptor (GHS-R1a/ghrelin receptor) on pituitary somatotrophs. It acts via dual sites — pituitary and hypothalamic — possibly involving regulatory factors beyond GHRH and somatostatin. GHRP-6 also stimulates ghrelin-mediated appetite signaling, increases cortisol and prolactin release, and has demonstrated cytoprotective properties including cardioprotection.

Standard Dosing

Research indicates 100-300 mcg administered 1-3 times daily via subcutaneous injection.

Timing

On empty stomach, 30+ minutes before meals. Bedtime dose most important. The strong hunger effect makes pre-meal timing practical.

Cycle Duration

8-16 week cycles.

Side Effects

  • Intense hunger (primary distinguishing side effect)
  • Water retention
  • Cortisol elevation
  • Prolactin elevation
  • Tingling and numbness
  • Injection site pain

Contraindications

  • Active cancer
  • Obesity (significant appetite stimulation)
  • Cushing's syndrome
  • Pregnancy and breastfeeding

Best Stacking Partners

CJC-1295 (no DAC)Sermorelin
B

Melanotan II

Peptides

Mechanism

Melanotan II is a synthetic cyclic analog of alpha-melanocyte-stimulating hormone (alpha-MSH) that non-selectively agonizes melanocortin receptors MC1, MC3, MC4, and MC5. MC1R activation stimulates eumelanin synthesis through tyrosinase upregulation, producing tanning. MC3R activation in the CNS increases libido and produces erectile responses. MC4R activation suppresses appetite. The cyclic structure provides enhanced in vivo stability (half-life 1-2 hours) and increased blood-brain barrier permeability compared to linear alpha-MSH.

Standard Dosing

Research indicates 250-500 mcg daily via subcutaneous injection during loading, reducing to 250 mcg 2-3 times weekly for maintenance.

Timing

Administer 4-6 hours before UV exposure for optimal tanning synergy. Can be taken at any time of day.

Cycle Duration

Loading phase 1-2 weeks, then maintenance as long as desired. Pigmentation fades gradually upon discontinuation.

Side Effects

  • Nausea (common, especially during loading)
  • Facial flushing
  • Spontaneous erections
  • Appetite suppression
  • Darkening of existing moles (monitor closely)
  • Fatigue
  • New nevus formation

Contraindications

  • History of melanoma or atypical moles
  • Active skin cancer
  • Pregnancy and breastfeeding
  • Addison's disease
  • Pheochromocytoma

Best Stacking Partners

PT-141

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