Sermorelin vs CJC-1295 vs Ipamorelin: Which GH Peptide for Your Research Goal?
Sermorelin, CJC-1295 (No-DAC) and Ipamorelin compared: half-life, GH profile, selectivity and evidence. The decision guide for researchers.
Anyone working in the field of GH secretagogues faces a concrete choice early on: Sermorelin, a CJC-1295-based stack or Ipamorelin? All three stimulate the body's own release of growth hormone (GH) rather than delivering GH directly. They differ markedly, though, in receptor, half-life, GH pulse profile, side-hormone cleanliness and the available evidence.
This guide is a decision aid, not a mechanism textbook. If you first want to understand the molecular basics (GHRH receptor vs ghrelin receptor, signaling pathways, synergy), read the detailed background in GHRH vs GHRP compared. Here the focus is on which of the three options fits which research goal.
TL;DR: The quick decision
Sermorelin: the best-documented, gentle GHRH base with a physiological nighttime pulse. CJC-1295 (No-DAC) + Ipamorelin: the synergistic stack with the strongest pulsatile GH response. Ipamorelin solo: the cleanest single secretagogue, with virtually no rise in cortisol or prolactin. Important: Our "CJC-1295" is the No-DAC blend with Ipamorelin, not a long-acting DAC depot and not a standalone CJC.
For research purposes only
This text places research peptides in the context of the GH axis. It is not medical advice, not a recommendation for human use and does not replace consultation with a physician. None of the peptides mentioned is an approved medicinal product for the purposes described here.
Quick selection by research goal
Best documentation, gentle physiological profile
Maximum pulsatile GH response via the synergy stack
The three options in detail
Sermorelin: the established GHRH base
Sermorelin is GHRH(1-29), the shortest biologically active fragment of the natural growth-hormone-releasing hormone. It activates the GHRH receptor on the somatotropic cells of the pituitary and triggers a pulsatile, physiological GH release there. Because it works through the natural signaling pathway, the negative feedback loop stays intact: somatostatin and IGF-1 can continue to regulate the output.
Pharmacokinetically, GHRH(1-29) is eliminated rapidly after IV administration (on the order of minutes), but the GH response remains measurably elevated for roughly 3 hours; maximum release occurred at 1-2 mcg/kg IV [PMID 8329825].
The most robust long-term evidence comes from a 16-week study in older adults using a very closely related GHRH(1-29) analogue ([Nle27]GHRH(1-29), 10 mcg/kg subcutaneously every evening at 21:00): IGF-1 rose significantly within 2 weeks and remained elevated, lean body mass increased in men, skin thickness in both sexes, and the only adverse effect was a transient, reversible hyperlipidemia [PMID 9141536].
Putting the study in context
The 16-week data come from a [Nle27] analogue that is very close to Sermorelin but not chemically identical. It is a strong proxy for the GHRH(1-29) class, but should not be read one-to-one as pure Sermorelin data.
Bottom line: of the three options, Sermorelin has the broadest human evidence base and the gentlest, most physiological profile.
GHRH(1-29) analog for physiological growth hormone stimulation research
CJC-1295 (No-DAC) + Ipamorelin: the synergy stack
CJC-1295 is GHRH(1-29) with four stabilizing amino acid substitutions (among them D-Ala at position 2, which blocks DPP-IV degradation) [PMID 7962295]. It binds the same GHRH receptor as Sermorelin but is metabolically hardened. The key distinction is between the two market forms:
- With DAC (Drug Affinity Complex): an albumin linker turns the peptide into a slow depot. A single subcutaneous injection kept GH 2- to 10-fold elevated for at least 6 days and IGF-1 1.5- to 3-fold for 9-11 days, with a half-life of 5.8-8.1 days [PMID 16352683]. The price for this: a non-pulsatile, multi-day exposure.
- Without DAC (also "Mod GRF 1-29" / "CJC-1295 No-DAC"): the same substitutions, but no albumin linker. It behaves like a short-acting GHRH analogue with a sharp pulse and rapid clearance.
Why we carry the No-DAC form, not DAC
The DAC variant produces a multi-day, steady GH/IGF-1 elevation instead of physiological pulses, and its Phase II program was discontinued in 2006. The shorter-acting No-DAC form respects the pulsatile pattern and the feedback loop. The half-life of the No-DAC form (often quoted at about 30 minutes) is based on the DPP-IV-resistant substitutions and secondary sources, not on a dedicated human PK study. Treat that value as an estimate.
The real reason for the combination is synergy: a GHRH signal (CJC-1295) and a GHRP signal (Ipamorelin) engage two different receptors on the same cell, and the GHRP additionally lowers the inhibitory somatostatin tone. In humans it is documented that combining GHRH with a GHRP produces a markedly stronger, pulsatile GH response than either component alone [PMID 19240251].
Limits of the synergy data
The synergy is established as a principle in humans [PMID 19240251], but there is no clean "X-fold over single substance" figure and no study specifically on Ipamorelin + CJC-1295. The mechanistic argument is solid, the exact magnitude in humans is not.
This stack is the choice when the goal is the maximum pulsatile GH output with a clean side-hormone profile and several injections per day are acceptable.
2-in-1 growth hormone blend: CJC-1295 no-DAC (Modified GRF 1-29, 5 mg) + Ipamorelin (5 mg) combined in one vial. The CJC-1295 component is the short-acting no-DAC variant (about 30 minute half-life), not the long-acting DAC form. Stimulates natural GH release through two different pathways for amplified, more physiological growth hormone pulses.
Ipamorelin: the selective single secretagogue
Ipamorelin is a pentapeptide and an agonist at the ghrelin receptor (GHS-R1a), making it a GHRP. Its unique feature is selectivity: in the defining study it triggered no relevant rise in ACTH, cortisol or prolactin even at more than 200 times the GH ED50, unlike the older GHRP-6 or GHRP-2 [PMID 9849822]. In human PK, the terminal half-life was around 2 hours, with a clear GH pulse (peak after roughly 40 minutes) and dose-proportional behavior [PMID 10496658].
Limits of the evidence
For Ipamorelin there is a solid human PK study, but no published long-term study on body composition in humans; a Phase II program was discontinued. The potency figures come from porcine and in-vitro data [PMID 9849822]. A body-composition benefit is therefore mechanistically plausible but not proven in human studies.
Ipamorelin solo is the choice when a single, especially clean secretagogue is wanted, rather than a two-vial combination.
Highly selective growth hormone releaser that triggers natural GH pulses without raising cortisol or prolactin. Clean GH stimulation with minimal side effects - the most targeted growth hormone peptide available.
Direct comparison at a glance
| Property | Sermorelin | CJC-1295 No-DAC (+ Ipamorelin) | Ipamorelin |
|---|---|---|---|
| Class / receptor | GHRH-R agonist | GHRH-R agonist (stabilized) + GHS-R1a | GHS-R1a / ghrelin receptor |
| Half-life | Minutes range [8329825] | approx. 30 min (estimated) + approx. 2 h | approx. 2 h [10496658] |
| GH profile | Sharp physiological pulse | Amplified, synergistic pulse | Clean single pulse |
| Injection frequency | Daily, often in the evening | 1-3x daily | 1-3x daily |
| Side-hormone cleanliness | Preserves feedback, clean | Clean (GHRP component = Ipamorelin) | Cleanest: no cortisol/prolactin [9849822] |
| Human evidence | Strongest [8329825, 9141536] | Synergy principle established [19240251] | Good PK, no long-term effect study [10496658] |
| In our shop as | Single peptide | No-DAC blend with Ipamorelin | Single peptide |
What we deliberately do not carry
A standalone CJC-1295 and the long-acting DAC variant are not in the range. Anyone researching "CJC-1295" uses the No-DAC blend with Ipamorelin at our shop, because GHRH alone is rarely run on its own and the No-DAC profile preserves pulsatility.
Which option fits which research goal?
You want the best-documented, gentle option
Sermorelin. The broadest human evidence base of the three, a physiological nighttime pulse, preserved feedback [PMID 8329825, 9141536].
You want the strongest pulsatile GH response
CJC-1295 No-DAC + Ipamorelin. The GHRH arm delivers the base signal, the GHRP arm amplifies the pulse and lowers somatostatin [PMID 19240251]. You accept several injections per day.
You want a single, especially selective secretagogue
Ipamorelin. The cleanest GH pulse with virtually no cortisol, prolactin or ACTH spillover [PMID 9849822], one substance instead of a blend.
Dosing: an honest research context
Study doses vs community protocols
From the primary literature (verified): GHRH(1-29) acute 1-2 mcg/kg IV [PMID 8329825]; GHRH(1-29) analogue chronic 10 mcg/kg subcutaneously in the evening over 16 weeks [PMID 9141536]; CJC-1295 DAC 30-60 mcg/kg per single injection [PMID 16352683]; Ipamorelin dose-proportional across a broad IV range in human PK [PMID 10496658].
From community and supplier sources (not validated by studies): No-DAC + Ipamorelin often at about 100 mcg each per dose, 1-3x daily, with at least one dose before sleep and on an empty stomach (food, especially carbohydrates and fat, blunts the GH pulse). These protocols do not come from controlled studies and are to be understood solely as research context.
Frequently asked questions
The substances described here are research peptides and carry different regulatory status depending on the compound. This article serves educational purposes only, is not medical advice and is not to be understood as a recommendation for human use.
Research context for English-speaking buyers
Most of our English-speaking customers ship to the UK, Ireland, Malta or other English-as-second-language EU territories. The regulatory picture differs per country.
- Relevant authorities
- MHRA (UK, post-Brexit), HPRA (Ireland, EU-aligned), FDA Section 503A bulks list (US, restricted Cat 2 status of several peptides as of 2026)
- Customs and VAT
- EU shipments include 19% VAT; UK shipments after Brexit are now extra-EU and may attract UK VAT plus a handling fee at import
- Typical shipping window
- EU 2-4 working days, UK 4-7 working days, other international 7-14 working days, depending on customs
Research-grade peptides shipped from our EU warehouse are sold for laboratory use only and are not authorised for human or veterinary therapeutic application in any of the destination jurisdictions. US customers should be aware that the FDA Section 503A bulks list classification (and the April 2026 reclassification of twelve compounds) only governs compounding pharmacies, not direct-to-researcher imports for non-clinical work. UK buyers should declare the consignment on import and may be asked for a research justification by HMRC. We provide a CoA per batch identified by colour code rather than serial number; customs sometimes asks for this document when clearing the parcel.