Ipamorelin
Selective GH secretagogue that stimulates GH without significantly raising cortisol or prolactin.
🔬 Mechanism of Action
Ipamorelin is a highly selective growth hormone secretagogue peptide (GHSP) that acts as a ghrelin receptor (GHS-R1a) agonist. Its defining characteristic is selectivity: unlike GHRP-6 and GHRP-2, Ipamorelin stimulates GH release without significantly elevating cortisol, prolactin, or appetite. This makes it the "cleanest" GH secretagogue available.
Ipamorelin stimulates the pituitary gland to release stored GH in a pulsatile pattern that mimics natural physiology. It is often combined with CJC-1295 (no DAC) for a synergistic GHRH + GHRP effect that maximizes GH output while maintaining a physiological release pattern.
Source: PMID: 9849822
📜Background & History
Ipamorelin was discovered by Novo Nordisk researchers in 1998 (Raun et al., European Journal of Endocrinology) as part of a systematic GHRP screening program seeking selectivity. Its defining innovation was near-complete selectivity for GH release without affecting cortisol, prolactin, or ACTH — side effects that plagued first-generation GHRPs (GHRP-6, GHRP-2). This selectivity profile made it the preferred GH secretagogue for research and clinical investigation. It remains the most widely used GHRP in wellness medicine.
🎯 Research Use Cases
- ✓Clean GH pulse stimulation without cortisol elevation
- ✓Sleep quality improvement via GH-mediated slow-wave sleep enhancement
- ✓Body recomposition: lean muscle gain and fat oxidation
- ✓Recovery acceleration appropriate for long-term use
- ✓Anti-aging GH restoration in somatopause
💉 Dosing Protocol
| Typical Dose | 100-300 mcg/injection |
| Frequency | 1-3× daily |
| Half-Life | ~2 hours |
| Common Vial Sizes | 2 mg, 5 mg |
🧪 Reconstitution Example
⚠️Safety & Considerations
Research peptide with a favorable safety profile in studies. May cause transient headache or lightheadedness. Minimal effect on cortisol, prolactin, or appetite (unlike GHRP-6). Inject on an empty stomach for optimal GH pulse.
⚡Interactions & Contraindications
Inject on empty stomach — food/insulin blunts response by 60–80%. Do not combine with growth hormone if IGF-1 is already elevated. Somatostatin analogs (octreotide) antagonize GH release. Hypothyroidism reduces GH receptor sensitivity — address thyroid function first.
🔗Synergies & Common Stacks
The most popular GH secretagogue stack: Mod GRF amplifies pulse amplitude while Ipamorelin provides the clean selective stimulation. Produces 2–5× more GH than either alone.
For convenience-focused protocols: once-weekly CJC-1295 DAC with daily Ipamorelin injections. Provides sustained baseline GH with clean daily pulses.
Recovery stack combining systemic tissue repair (BPC-157) with GH-mediated anabolic and regenerative signals (Ipamorelin).
❓ Frequently Asked Questions
What makes Ipamorelin better than GHRP-6?▼
What is the standard Ipamorelin dose?▼
How long does it take to see results from Ipamorelin?▼
📖 References
- Raun K, et al. “Ipamorelin, the first selective growth hormone secretagogue.” Eur J Endocrinol (1998). PMID: 9703375
- Gobburu JV, et al. “Safety and tolerability of ipamorelin in healthy subjects.” Growth Horm IGF Res (2009). PMID: 19411194