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BiologicalX

Comparison

Ipamorelin vs Melatonin

Side-by-side of Ipamorelin and Melatonin. Every row below is pulled from the compound schema and will update as our data grows. For deeper reads, follow through to each compound page.

Effects at a glance

Ipamorelin

  • Pentapeptide GHS-R1a agonist with the cleanest selectivity profile in the GHRP class
  • Minimal cortisol and prolactin elevation at standard doses (substantially less than GHRP-2 or hexarelin)
  • ~2 hour plasma half-life, longest of the synthetic GHRPs
  • Largest human safety database (~600 participants in Helsinn's postoperative ileus phase 2)
  • Standard pairing for CJC-1295 no-DAC at 200 to 300 mcg subcutaneously 2 to 3 times daily
  • Banned by WADA under S2; never reached registration despite phase 2b development

Melatonin

  • Shortens sleep onset latency by ~7 to 12 minutes at physiological 0.3 to 1 mg doses
  • Advances circadian phase when taken 30 to 60 minutes before target bedtime, useful for jet lag and shift work
  • Does not meaningfully increase total sleep time in healthy adults without circadian misalignment
  • Endogenous nighttime production is not suppressed by short-term exogenous supplementation
  • Higher doses (3 to 10 mg) raise plasma levels above physiological range and often increase morning grogginess
  • Effective for delayed sleep-wake phase disorder and reducing jet-lag severity in eastward travel

Side-by-side

Attribute Ipamorelin Melatonin
Category peptide supplement
Also known as NNC 26-0161, Aib-His-D-2-Nal-D-Phe-Lys-NH2 N-acetyl-5-methoxytryptamine
Half-life (hr) 2 0.75
Typical dose (mg) 0.2 0.5
Dosing frequency 2-3x daily daily, 30 to 60 minutes before target sleep time
Routes subcutaneous, intravenous oral, sublingual
Onset (hr) 0.25 0.5
Peak (hr) 1 1
Molecular weight 711.86 232.28
Molecular formula C38H49N9O5 C13H16N2O2
Mechanism Selective GHS-R1a agonist that stimulates pulsatile GH release with minimal cortisol or prolactin co-activation. Suppresses hypothalamic somatostatin and stimulates pituitary somatotrophs. Agonist at MT1 and MT2 receptors in the suprachiasmatic nucleus, signaling biological night and promoting sleep-onset gating plus circadian phase shifts.
Legal status Not FDA approved; advanced through phase 2b in postoperative ileus before discontinuation; research-use-only grey market; banned by WADA OTC in US; prescription in UK, EU, Japan
WADA status banned allowed
DEA / Rx Not scheduled (research chemical) OTC supplement in US; Rx in UK, EU, Japan, Australia
Pregnancy Insufficient data; not recommended Insufficient data; not routinely recommended
CAS 170851-70-4 73-31-4
PubChem CID 11338566 896
Wikidata Q1666741 Q179243

Safety profile

Ipamorelin

Common side effects

  • injection-site irritation
  • vivid dreams
  • transient mild head pressure
  • occasional headache

Contraindications

  • pregnancy
  • active malignancy
  • history of pituitary tumor
  • uncontrolled diabetes

Interactions

  • CJC-1295: synergistic GH release via parallel GHRH and ghrelin pathways; standard pairing(minor)
  • sermorelin: additive GH release; functionally similar pairing to CJC-1295 with shorter GHRH half-life(minor)
  • insulin: sustained GH can blunt insulin sensitivity over weeks(moderate)
  • corticosteroids: blunt GH response; reduce expected efficacy(moderate)

Melatonin

Common side effects

  • vivid dreams
  • morning grogginess (higher doses)
  • headache
  • dizziness

Contraindications

  • autoimmune disease (theoretical)
  • concurrent anticoagulant therapy without monitoring

Interactions

  • fluvoxamine: CYP1A2 inhibition raises melatonin levels substantially(major)
  • warfarin: possible increased bleeding risk(moderate)
  • benzodiazepines and alcohol: additive sedation(moderate)
  • antihypertensives: may alter blood pressure response(minor)

Which Should You Take?

Melatonin comes out ahead for most readers on the criteria we weight: 2 catalogued goals, OTC, oral dosing, with a Tier-A outcome catalogued. Ipamorelin is the right call when one of the conditionals below applies.

  • If your priority is growth-hormone axis, pick Ipamorelin.
  • If your priority is post-training recovery, pick Ipamorelin.
  • If your priority is sleep onset or sleep quality, pick Melatonin.
  • If your priority is circadian regulation, pick Melatonin.

Edge case: If you want to avoid research-only / gray-market sourcing, Melatonin is the more accessible choice.

Default choice: Melatonin. Wider use case, a Tier-A evidence outcome catalogued, and broader goal coverage. Reach for Ipamorelin only if your priority sits squarely in the goals it owns above.

This verdict is generated from each compound's schema (goals, legal status, evidence outcomes, dosing route). It updates automatically as our compound data evolves; the deeper read sits on each individual compound page.

Common questions

What is the difference between Ipamorelin and Melatonin?

Ipamorelin and Melatonin differ in category (peptide vs supplement), mechanism, and typical dosing. See the side-by-side table for full details.

Which has a longer half-life, Ipamorelin or Melatonin?

Ipamorelin half-life is 2 hours; Melatonin half-life is 0.75 hours.

Can you stack Ipamorelin with Melatonin?

Stack compatibility depends on mechanism overlap, legal status, and individual response. Check each compound page for specific interactions and contraindications before combining.

Go deeper