Compound Guide• 6 min read
Ipamorelin vs CJC-1295: GHRH Analog vs GH Secretagogue Research
Ipamorelin and CJC-1295 are the two most-stacked growth-hormone peptides in research. They work on different receptors, produce complementary GH pulses, and together generate a larger response than either compound alone.
Mechanism: different receptors, same downstream goal
Ipamorelin is a selective ghrelin receptor (GHS-R) agonist — a growth-hormone-releasing peptide (GHRP). It triggers a GH pulse from the anterior pituitary without significantly elevating cortisol or prolactin, which is why it became preferred over earlier GHRPs like GHRP-6.
CJC-1295 is a synthetic analog of GHRH (growth-hormone-releasing hormone). It binds the GHRH receptor and amplifies the pituitary's natural GH-release rhythm. The DAC (Drug Affinity Complex) variant binds albumin for an extended half-life.
Half-life comparison
- Ipamorelin: ~2-hour half-life — produces a discrete GH pulse
- CJC-1295 (no DAC, also called Mod GRF 1-29): ~30-minute half-life — pairs naturally with ipamorelin's pulse window
- CJC-1295 DAC: ~6–8 day half-life — produces sustained elevation of basal GH and IGF-1 levels in published research
Why labs stack ipamorelin with CJC-1295
GHRH analogs prime the pituitary to release more GH per pulse, while GHRPs trigger the pulse itself. Published work shows the combination produces a synergistic GH response — substantially larger than the sum of either peptide alone.
FAQ
What is the difference between CJC-1295 with and without DAC?
With DAC, the peptide binds albumin for multi-day half-life and sustained GH elevation. Without DAC (Mod GRF 1-29), the half-life is short and produces a discrete pulse that mirrors natural GHRH.
Is ipamorelin the cleanest GHRP?
It is the most selective GHRP in published literature — no measurable cortisol or prolactin elevation at standard research doses, which is its main advantage over GHRP-2 and GHRP-6.