Ipamorelin vs Melanotan II

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

IpamorelinMelanotan II
CategoryPeptidesPeptides
Standard DoseResearch indicates 200-300 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.
TimingBest administered at bedtime for synergy with natural GH peak. Also effective upon waking and post-workout. Always on empty stomach.Administer 4-6 hours before UV exposure for optimal tanning synergy. Can be taken at any time of day.
Cycle Duration12-24 week cycles with 4-8 week breaks.Loading phase 1-2 weeks, then maintenance as long as desired. Pigmentation fades gradually upon discontinuation.
Evidence Levelmoderate_humanmoderate_human
A

Ipamorelin

Peptides

Mechanism

Ipamorelin is a pentapeptide (Aib-His-D-2-Nal-D-Phe-Lys-NH2) that acts as the first selective growth hormone secretagogue receptor (GHS-R1a/ghrelin receptor) agonist. Unlike other GHRPs, it selectively stimulates GH release without significantly affecting ACTH, cortisol, prolactin, or aldosterone — even at doses 200-fold above the ED50 for GH release. This selectivity profile is comparable to GHRH itself but operates through the distinct ghrelin receptor on pituitary somatotrophs.

Standard Dosing

Research indicates 200-300 mcg administered 1-3 times daily via subcutaneous injection.

Timing

Best administered at bedtime for synergy with natural GH peak. Also effective upon waking and post-workout. Always on empty stomach.

Cycle Duration

12-24 week cycles with 4-8 week breaks.

Side Effects

  • Head rush post-injection
  • Mild hunger increase (less than GHRP-6)
  • Water retention (mild)
  • Tingling in extremities
  • Injection site irritation

Contraindications

  • Active cancer
  • Diabetic retinopathy
  • Pregnancy and breastfeeding

Best Stacking Partners

CJC-1295 (no DAC)BPC-157TB-500
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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