CJC-1295 / Ipamorelin

A two-part growth-hormone-axis blend: CJC-1295, a GHRH analogue that raises the standing drive to the pituitary, paired with Ipamorelin, a selective GH secretagogue that adds a clean, sharp pulse on top.

What it is

CJC-1295 / Ipamorelin combines two peptides that act on the growth-hormone axis through different receptors. CJC-1295 is an analogue of the first 29 amino acids of growth-hormone-releasing hormone (GHRH), the shortest fragment of native GHRH that keeps full activity, engineered for a longer duration of action. Ipamorelin is a pentapeptide (Aib-His-D-2-Nal-D-Phe-Lys-NH2) and was described by Raun and colleagues in 1998 as the first selective growth-hormone secretagogue, meaning it drives GH release with little effect on other pituitary hormones.

The two are studied together because they pull on complementary levers. GHRH analogues and GH secretagogues (ghrelin-receptor agonists) act on separate receptors on the same pituitary somatotroph cells, so pairing them is investigated for a larger, more synergistic GH response than either peptide produces alone. Supplied strictly for laboratory research use only, not for human or veterinary use.

How it works

CJC-1295 binds the pituitary GHRH receptor, a G-protein-coupled receptor that raises intracellular cyclic AMP and prompts the somatotrophs to synthesise and release growth hormone. This is the same pathway used by native GHRH, so CJC-1295 is studied as a way to lift the underlying tone of the GH axis while preserving the pituitary's own feedback rhythm.

Ipamorelin acts on a different target, the growth-hormone secretagogue receptor (GHS-R1a), the same receptor that binds ghrelin. Activating this receptor triggers a separate intracellular cascade that both amplifies GH release and eases somatostatin, the brake on the system. Because the two peptides engage GHRH-R and GHS-R1a at once, their signals converge on the somatotroph and are studied for an additive or synergistic effect on GH output. In the Raun work, Ipamorelin's defining feature was selectivity: even at doses more than 200-fold above its effective dose for GH release, it did not raise ACTH or cortisol above the levels seen with GHRH, and it did not affect FSH, LH, prolactin or TSH.

What the research shows

The two components have been characterised separately in the literature. For CJC-1295, the key human data come from Teichman and colleagues (2006), a pair of randomised, double-blind, placebo-controlled ascending-dose trials in healthy adults published in the Journal of Clinical Endocrinology & Metabolism. A single subcutaneous dose raised mean GH by roughly 2- to 10-fold for six days or more and mean IGF-1 by 1.5- to 3-fold for 9 to 11 days, with IGF-1 staying above baseline for up to 28 days after multiple doses. For Ipamorelin, Raun and colleagues (1998) quantified potency in vitro and in swine and established its selective profile.

Why the pairing is studied

The rationale for combining a GHRH analogue with a GH secretagogue is that they act through two distinct receptors on the somatotroph. CJC-1295 raises the standing GHRH drive while Ipamorelin adds a ghrelin-receptor pulse and eases the somatostatin brake, so investigators study the pair for a GH response greater than the sum of the individual peptides. Ipamorelin's selectivity is part of the appeal in this context: unlike earlier secretagogues such as GHRP-6 and GHRP-2, it did not meaningfully raise ACTH, cortisol or prolactin in the Raun studies, which is why it is described as the first selective GH secretagogue.

Side Effects

No controlled human trial has tested the CJC-1295 and ipamorelin combination directly, so a validated safety profile for the exact stack does not exist. The entries below are drawn from the individual peptides and from the broader growth-hormone-secretagogue and GH-excess literature, and class-based extrapolations are labeled as such. Reported effects are generally mild and dose-related in the source studies, but individual response is not established for this pairing.

To be clear, no controlled human trial has established the safety or tolerability of the CJC-1295 plus ipamorelin combination itself. Every entry above is inferred from the individual peptides or from the wider growth-hormone-secretagogue class, so real-world tolerability for this specific stack remains uncharacterized.

At a glance

Dosing

There is no approved or clinically established dosing regimen for the CJC-1295 plus ipamorelin combination. No controlled trial has studied the two peptides together in humans, so the figures below are the doses each peptide received in its own separate studies, reported in weight-based terms as published. They are shared as educational context about the research record, not as instructions for use.

No published trial has established a combined regimen, so any pairing of these figures is an extrapolation from separate single-peptide studies rather than a validated protocol. This information is provided for laboratory research use only and is not medical guidance.

Preparing it

The blend ships as a lyophilized powder and is reconstituted with bacteriostatic water (or sterile water for single-session work) before use. Both peptides go into solution together; draw the diluent slowly down the side of the vial and swirl gently, never shake, until fully dissolved. Choose a volume that gives a concentration convenient to read on a U-100 syringe. See reconstitution for the step-by-step method and the concentration formula for working out how much diluent to add.

Where to go next

Last updated on July 3, 2026