CJC-1295 + Ipamorelin: Two different paths to the growth-hormone axis

People pair these two because they sound complementary: one for a longer baseline, one for a pulse. The papers are more precise than the forums. CJC-1295 is a growth-hormone-releasing-hormone analog with a Drug Affinity Complex that binds albumin, stretching the half-life into days. Ipamorelin is a five-residue ghrelin-receptor agonist. They do not bind the same receptor. They do not last the same amount of time. A blend is a purchasing convenience — two sequences in one tube — not a new molecule.

What Teichman measured in people

In 2006, Teichman and colleagues gave healthy adults subcutaneous CJC-1295 in randomized, placebo-controlled, ascending-dose work. After one injection, mean plasma GH rose 2- to 10-fold for six days or more, and mean IGF-I rose 1.5- to 3-fold for nine to eleven days. Estimated half-life: 5.8 to 8.1 days. After several doses, IGF-I stayed above baseline for up to 28 days. A companion paper by Ionescu and Frohman showed the pituitary still pulsed. What rose hard was the trough. That trough, not a taller spike, tracked the IGF-I increase — a detail that softens some of the simpler “night pulse” storytelling online.

What Raun measured that set ipamorelin apart

Ipamorelin was published in 1998 as the first GHRP-receptor agonist with GHRH-like selectivity for GH. In rat pituitary cells it released GH with potency in the same neighborhood as GHRP-6. In anaesthetized rats and in swine it did the same. The difference: GHRP-6 and GHRP-2 also moved ACTH and cortisol. Ipamorelin did not, even at doses more than two hundred times the GH ED50. That selectivity is why it became the “clean” secretagogue in later catalogs. Clean, in that paper, means a hormone panel in animals — a specific preclinical finding worth taking on those terms.

Two receptors, two time scales — and one vial that still asks you to read two papers.