Two Receptors, One Stack
The CJC-1295 + Ipamorelin stack is the most-studied GH axis research pair because it engages two orthogonal receptors simultaneously — amplifying GH pulse amplitude (CJC-1295) while preserving or enhancing pulsatility (Ipamorelin).
Both compounds ship together as CJC-1295 + Ipamorelin for paired research protocols.
CJC-1295: GHRH Receptor Research
CJC-1295 is a modified GHRH analog. The modifications relevant to research:
- Drug Affinity Complex (DAC) form: Binds albumin for extended half-life (~8 days)
- No-DAC form: Native half-life (~30 minutes), pulsatile kinetics
- Mechanism: Binds the GHRH receptor on anterior pituitary somatotrophs, increasing GH release
The choice between DAC and no-DAC forms is the primary research design decision — DAC produces sustained elevation; no-DAC preserves natural pulse rhythm.
Ipamorelin: Ghrelin Receptor Research
Ipamorelin is a selective GHS-R1a (ghrelin receptor) agonist. What makes it research-relevant:
- Selectivity: Binds GHS-R1a without meaningful engagement of other ghrelin-sensitive receptors
- Lack of cortisol or prolactin elevation — unlike earlier GHS-R agonists
- Short half-life (~2 hours): Enables pulsatile protocol design
The selectivity matters because first-generation ghrelin receptor compounds produced off-target endocrine effects that confounded GH-axis research.
Why Pulsatility Matters More Than Amplitude
GH secretion is inherently pulsatile — and the downstream IGF-1 response depends on pulse architecture, not just cumulative GH concentration. Research that flattens the pulse pattern (through sustained GH elevation) produces a different IGF-1 and receptor-desensitization profile than research that preserves pulsatility.
This is the reason most research uses no-DAC CJC-1295 with Ipamorelin — both compounds have half-lives compatible with pulsatile dosing rhythm.
Research Outcomes to Track
- GH pulse amplitude and frequency
- IGF-1 levels — the downstream integrated readout
- IGFBP-3 — the primary IGF-1 binding protein
- Secondary markers: fat-free mass, recovery kinetics, sleep architecture
Timing and Cadence
The most-studied protocol is twice- or thrice-daily dosing separated by at least 3–4 hours — spacing that respects pulse biology and avoids receptor desensitization.
Sourcing the Paired Stack
Since the two compounds are nearly always studied together, a pre-paired format simplifies protocol logistics. See CJC-1295 + Ipamorelin for the paired research vial.