Pulse & sustain — the GH stack
Ipamorelin was first described in a landmark 1998 paper by Raun et al. as "the first selective growth hormone secretagogue" — notable because it stimulated GH release without the cortisol, prolactin, or ACTH elevations seen with earlier GH secretagogues like GHRP-2 and GHRP-6. That selectivity made it uniquely clean for body composition applications.
CJC-1295 is a GHRH analogue with a Drug Affinity Complex (DAC) modification — a chemical anchor that binds to albumin in the bloodstream and dramatically extends its half-life from minutes to 6–8 days. A 2006 Phase II trial in healthy adults by Teichman et al. (published in JCEM) showed that a single dose produced sustained, dose-dependent increases in GH and IGF-1 lasting up to 28 days — a landmark result for a GHRH analogue.
Neither compound is FDA-approved as a drug. They are available through compounding pharmacies and are among the most prescribed peptides at anti-ageing and functional medicine clinics globally. The combination emerged from the logic that CJC-1295 sustains the GHRH signal while ipamorelin amplifies individual GH pulses — covering two complementary aspects of GH physiology simultaneously.
The "pulse and sustain" mechanism: CJC-1295 maintains an elevated GHRH baseline over days, priming the pituitary. Ipamorelin then triggers sharp GH pulses through a completely different receptor (GHSR — the ghrelin receptor). Studies suggest the combination produces 3–5x more GH release than either compound alone, because they activate two distinct pathways simultaneously.