Quick Comparison
| CJC-1295 | Ipamorelin | |
|---|---|---|
| Class | GHRH analog | Ghrelin receptor agonist (GHRP) |
| Receptor | GHRH receptor | Ghrelin/growth hormone secretagogue receptor |
| Half-life | With DAC: several days. Without DAC (Mod GRF 1-29): ~30 minutes | Short, dosed multiple times per day or per protocol |
| Typical dosing frequency | With DAC: once or twice weekly. Without DAC: frequent, similar to Sermorelin | Frequent, similar to other GHRPs |
| FDA status | Not FDA-approved, research chemical only | Not FDA-approved, research chemical only |
| Common pairing | Most often paired with Ipamorelin | Most often paired with CJC-1295 |
What Each Compound Is
CJC-1295 is a synthetic analog of growth-hormone-releasing hormone (GHRH). It comes in two forms. With DAC (Drug Affinity Complex), it binds serum albumin in the bloodstream, which extends its half-life to several days and allows infrequent dosing, roughly once or twice a week. Without DAC, also commonly called Mod GRF 1-29, it has a short half-life of around 30 minutes and is dosed more frequently, similar in pattern to Sermorelin.
Ipamorelin is a selective ghrelin receptor agonist, a peptide in the GHRP (growth-hormone-releasing peptide) category. It's generally studied as one of the more receptor-selective compounds in its class, with research suggesting a lower tendency to meaningfully raise cortisol or prolactin than older-generation GHRPs.
Mechanism: Why They're Stacked Together
CJC-1295 acts on the GHRH receptor, the same receptor family that Sermorelin works through. Ipamorelin acts on the ghrelin receptor, a separate receptor entirely. Because these are two different receptors that both converge on growth hormone release from the pituitary, combining them is common practice, and the two signals are generally understood to complement rather than duplicate each other.
Why this is the classic stack: CJC-1295 plus Ipamorelin is generally considered the more common GH-axis pairing, more so than Sermorelin plus Ipamorelin (covered in Ipamorelin vs Sermorelin). The dual-receptor logic is the same in both cases, but this particular pairing is the one most people mean when they talk about "the GH stack."
Human and Preclinical Evidence
Both compounds have an established body of research examining their individual mechanisms: CJC-1295's action at the GHRH receptor and its extended half-life when formulated with DAC, and Ipamorelin's selectivity at the ghrelin receptor relative to older-generation GHRPs. Much of the direct evidence on the combination itself comes from the shared logic of pairing a GHRH-receptor compound with a ghrelin-receptor compound, the same rationale documented for GHRH/GHRP combinations generally, rather than from CJC-1295-and-Ipamorelin-specific trials.
Neither compound's current research-chemical form is FDA-approved for human use, so both are evaluated against the broader body of GHRH and GHRP peptide research rather than against dedicated drug-approval trials for this specific combination.
Regulatory Status and Safety
Neither CJC-1295 nor Ipamorelin is FDA-approved as a prescription drug. Both are sold as research chemicals for laboratory research use only. As with any peptide protocol, a general safety baseline (comprehensive metabolic panel and CBC) before starting, and periodically during, is standard practice; see the peptide bloodwork guide for what a baseline panel typically includes.
What They Have in Common, and What's Different
In common: both are growth-hormone secretagogues aimed at restoring a more pulsatile pattern of GH release rather than supplying growth hormone directly, both are commonly dosed by subcutaneous injection, both are sold strictly as research chemicals, and both are tracked using the same downstream marker.
Different: the receptor each one acts on (GHRH receptor for CJC-1295, ghrelin receptor for Ipamorelin), the half-life and dosing frequency (especially for CJC-1295 with DAC, which is dosed far less often than Ipamorelin), and the selectivity profile Ipamorelin is specifically studied for around cortisol and prolactin.
Bloodwork to Track
IGF-1 is the standard marker for tracking growth-hormone-axis activity with either or both compounds, for the same reason it's used across GH-secretagogue protocols generally: growth hormone itself is released in short pulses that are hard to catch on a single blood draw, while IGF-1 reflects a more stable downstream signal. A baseline IGF-1 test before starting, and a follow-up around 8 to 12 weeks in, is the most direct way to see whether the stack is doing what it's supposed to. See the full peptide bloodwork guide for the rest of the core panel.
Choosing Between Them
This isn't really an either-or decision for most people. CJC-1295 and Ipamorelin target two different receptors and are generally used together rather than as substitutes for one another, which is why this pairing has become the more classic version of the GH-axis stack. Someone deciding between CJC-1295 with DAC versus without DAC is mostly weighing dosing frequency and half-life, not picking between CJC-1295 and Ipamorelin. BioStackIQ's Rate My Stack can score a stack that includes either or both against BioStackIQ's optimization categories, and Build Protocol can help lay out dosing and timing once a direction is chosen.