Ipamorelin
Research OnlyA growth hormone secretagogue that stimulates GH release without significant effects on cortisol or prolactin. Developed by Novo Nordisk (Denmark); limited clinical development despite promising early data.
NNC 26-0161 · NNC-26-0161
4 human studies
- Preclinical
- 50%
- Human research
- 22%
Based on 18 cited sources
Numeric assessment unreviewed
A historical numeric score is recorded but has not passed a current, compound-specific assessment review. No numeric score is displayed.
This is a limitation of the numeric assessment, not a measured absence of benefit. It does not re-review the separately recorded catalogue classification or establish efficacy or safety.
The proposed mechanisms of ipamorelin are based on clinical and preclinical studies. Human data exists but is limited to short-term Phase 1/2 trials.
How It Works (Simplified)
Ipamorelin acts as a selective growth hormone secretagogue through the ghrelin receptor:
Binds to the ghrelin receptor (GHS-R1a) on pituitary somatotrophs, triggering growth hormone release through Gq/11 protein activation.
Stimulates growth hormone secretion without elevating cortisol or prolactin levels, unlike older GH secretagogues (GHRP-6, GHRP-2).
Mimics natural GH release pattern with discrete pulses rather than constant elevation, preserving physiological hormone rhythms.
High receptor selectivity results in minimal side effects compared to less selective GH secretagogues, with no significant appetite stimulation.
Key Research: Raun K et al. (Novo Nordisk, Denmark, 1998) identified ipamorelin as first selective GH secretagogue. PMID:9849822
Important Limitations
- Not approved by FDA, EMA, or any regulatory agency
- Phase 2 clinical trial for post-operative ileus failed to meet primary endpoint
- Long-term safety data not available
- Prohibited in athletic competition by WADA
- Translation from preclinical to human outcomes is not fully established
Reported positives
- Improved sleep quality and deeper sleep reported
- Subtle body composition improvements over time
- Fewer side effects compared to other GH secretagogues
- Improved recovery from exercise reported
Reported negatives
- Effects subtle and slow to manifest
- Injection timing and fasting requirements inconvenient
- Head rush or flushing shortly after injection
- Results plateau after extended use
“Popular GH secretagogue considered milder than GHRP options. Often combined with CJC-1295.”
Self-reported, unverified accounts — not clinical evidence and no substitute for the cited research. Anecdotes are prone to selection bias and placebo effects.
| NCT ID | Title | Peptide | Phase | Status | Completion |
|---|---|---|---|---|---|
| NCT00672074 | Ipamorelin for Postoperative Ileus Ileus | Ipamorelin | Phase 2 | Completed | Dec 2009 (date type unverified) |
| NCT01280344 | Dose-Finding Study of Ipamorelin for Post-Surgical GI Recovery Gastrointestinal Dysmotility | Ipamorelin | Phase 2 | Completed | Jun 2013 (date type unverified) |
Ipamorelin for Postoperative Ileus
Dose-Finding Study of Ipamorelin for Post-Surgical GI Recovery
Based on Phase 1 data: GH release begins within 15-30 minutes of injection. Peak GH levels occur approximately 30-60 minutes post-injection. Effects are acute and pulsatile.
PMID:9849822With daily or twice-daily dosing, GH pulsatility patterns established. Early studies showed dose-dependent GH release without significant cortisol or prolactin elevation. No desensitization observed.
PMID:9849822Sustained GH/IGF-1 elevations with continued use. Gastrointestinal motility effects noted in post-operative trials. Body composition changes may begin to become apparent.
PMID:25331030Limited long-term data. Phase 2 POI trials used short-term administration. Extended use outcomes not well-characterized in clinical trials. No approved indications exist.
Research-based observations
This timeline reflects observations from published clinical and preclinical studies. Individual responses may vary significantly. This is not a guarantee of effects or a dosing schedule. Consult qualified healthcare providers for personalized guidance.
CJC-1295
SynergisticFrequently combined in research. Ipamorelin (ghrelin receptor) and CJC-1295 (GHRH receptor) act through complementary pathways, potentially producing additive GH release effects.
Sermorelin
SynergisticGHRH + GHRP synergy demonstrated in human studies. Sermorelin amplifies the GH pulse while ipamorelin initiates release. Combined effect may exceed either alone.
GHRP-6
CompatibleBoth act on ghrelin receptor with different selectivity profiles. Ipamorelin is more selective with less cortisol/prolactin effects. No clear benefit to combining same-mechanism agents.
GHRP-2
CompatibleSame receptor target (GHS-R1a). GHRP-2 is more potent but less selective. No established rationale for combination.
Semaglutide
CautionGH secretagogues may affect glucose metabolism. Monitor blood glucose if using with GLP-1 agonists in diabetic patients.
Research Note: Interaction data is based on published literature, mechanistic understanding, and theoretical considerations. Most peptide combinations lack direct clinical study. This information is for educational purposes only and does not constitute medical advice. Always consult qualified healthcare providers.
Key Studies Cited
Use the source links in the research discussion above to inspect the referenced records.
This dossier synthesizes available evidence from peer-reviewed literature, regulatory documents, and clinical trial registries. Evidence strength labels summarize the cited material for this entry and should be read alongside its population, model, and study limitations.
For complete methodology details, see our Methodology page.
Important Disclaimer
This dossier is for educational purposes only and does not constitute medical advice. Always consult a qualified healthcare provider before making health decisions.
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Compare Ipamorelin
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Compared With
7 comparisonsConditions Studied
6 entries- Ipamorelin for Growth Hormone Release Ipamorelin was designed by Novo Nordisk as a selective growth hormone secretagogue with minimal effects on cortisol and prolactin.…
- Ipamorelin for Anti-Aging Interest in ipamorelin for anti-aging stems from its ability to stimulate GH release while minimizing side effects. The selective…
- Ipamorelin for Sleep Improvement Ipamorelin is often combined with CJC-1295 in protocols targeting sleep improvement. GH secretion is closely linked to sleep archi…
- Ipamorelin for Recovery The GH/IGF-1 axis plays important roles in tissue repair and recovery. Ipamorelin's selective GH-releasing effect may support reco…
- Ipamorelin for Body Composition Growth hormone has well-documented effects on body composition, promoting fat loss and muscle preservation. Ipamorelin's GH-releas…
- Ipamorelin for Bone Health Scandinavian research groups studied ipamorelin's effects on bone metabolism. The GH/IGF-1 axis is important for bone formation an…
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