Research guide · CJC-1295 / Ipamorelin
CJC-1295 and Ipamorelin: what they are and where the research stands
Last updated: 27 August 2026
CJC-1295 and Ipamorelin are two peptides commonly studied together in growth-hormone-axis research. Their pairing is based on how the two act on different but complementary parts of the same signalling system.
This page covers what each is, how each is described in the research literature, where that research currently stands, and what to check before buying. It does not contain usage or dosing guidance.
Research use only · 18+What they are
A pair studied together on the GH axis
CJC-1295
Sequence: a synthetic peptide analogue of growth-hormone-releasing hormone (GHRH), often supplied as the shorter-acting CJC-1295 form (without the DAC affinity modification).
Research context: studied in preclinical and limited early human research as a GHRH-receptor agonist — a molecule that binds to and activates the GHRH receptor on pituitary cells.
Ipamorelin
Sequence: a synthetic pentapeptide.
Research context: studied as a growth-hormone secretagogue that binds to the ghrelin receptor (GHS-R1a), a different receptor to CJC-1295. Reported in the literature as selective for growth-hormone release with less activity on other pituitary hormones than earlier secretagogues.
The two are commonly investigated together because they act on different receptors within the same hormonal axis. In the research literature this dual-pathway approach is presented as a subject of study, not as a validated treatment protocol.
Regulatory status
Where the research stands
Both CJC-1295 and Ipamorelin are investigational. Neither has been authorised for medical use by the MHRA in the United Kingdom, by the EMA in Europe, or by the FDA in the United States.
That means:
- Neither is a licensed medicine in the UK.
- Neither can lawfully be sold or supplied for human use here.
- Anything offered for sale is supplied for laboratory research purposes only.
- Neither has completed the full regulatory review that licensed medicines undergo.
Both compounds are listed by WADA among substances prohibited in competitive sport, in the category of growth-hormone-releasing factors and peptide hormones. Any seller presenting either as an approved therapy is misrepresenting it.
The research literature
What has, and has not, been established
The published literature for both peptides consists primarily of preclinical work — cell culture experiments and animal studies — with a small number of early-phase human trials for CJC-1295 assessing endocrine effects.
What that literature describes:
- Effects on growth-hormone release observed in laboratory settings.
- Mechanistic pathways proposed on the basis of receptor pharmacology.
- Short-term endocrine outcomes in small early-phase studies.
What that literature does not establish:
- Safe or effective long-term use in humans.
- Dosing schedules for humans outside a research setting.
- Comparative effectiveness against approved growth-hormone-axis treatments.
- Any specific therapeutic indication.
Marketing that presents preclinical or small early-phase findings as evidence of routine human use is misrepresenting the underlying research.
What the research shows
Selected findings from the published literature
The CJC-1295 and Ipamorelin literature includes preclinical pharmacology work and several early-phase human studies conducted through the 1990s and 2000s. The findings below are drawn from peer-reviewed publications and are reported as observed in the referenced study — they do not describe therapeutic use outside a clinical-trial setting.
CJC-1295
2006Phase 1 · healthy adults
Prolonged stimulation of GH and IGF-I in healthy adults
After a single subcutaneous injection, mean plasma GH increased dose-dependently by 2- to 10-fold for 6 days or more, and mean plasma IGF-I increased 1.5- to 3-fold for 9–11 days. Estimated half-life was 5.8–8.1 days. After multiple doses, mean IGF-I remained above baseline for up to 28 days. CJC-1295 was described as safe and relatively well tolerated at 30–60 µg/kg, with no serious adverse reactions reported.
Teichman SL et al. J Clin Endocrinol Metab. 2006. PMID: 16352683. DOI: 10.1210/jc.2005-1536.
2009Clinical · healthy men
Activation of the GH/IGF-1 axis with associated serum-protein changes
Serum mean GH, lowest GH and IGF-1 all increased significantly at one week post-dose. Of 192 analysed protein spots, five changed significantly, with one spot correlating with IGF-1 (r² = 0.668; P = 0.002). Institutional review board approval was obtained; no adverse events were reported.
Sackmann-Sala L et al. Growth Horm IGF Res. 2009. PMCID: PMC2787983. DOI: 10.1016/j.ghir.2009.03.001.
Ipamorelin
1998Preclinical · discovery paper
Selective growth-hormone secretagogue characterisation
In rat pituitary cells, Ipamorelin showed EC₅₀ 1.3 ± 0.4 nmol/L and Emax 85 ± 5%. In anaesthetised rats, ED₅₀ was 80 ± 42 nmol/kg with Emax 1545 ± 250 ng GH/mL. Critically, Ipamorelin did not significantly increase ACTH or cortisol, and none of the secretagogues affected FSH, LH, PRL or TSH — indicating selective GH release even at doses more than 200-fold the GH ED₅₀.
Raun K et al. Eur J Endocrinol. 1998;139:552–61. PMID: 9849822. DOI: 10.1530/eje.0.1390552.
2014Phase 2 · postoperative
Randomised proof-of-concept study in bowel resection patients
Median time to first tolerated meal was 25.3 hours with ipamorelin vs 32.6 hours with placebo. Ipamorelin was reported as well tolerated, with treatment-emergent adverse event rates of 87.5% vs 94.8% for placebo. Trial registered on ClinicalTrials.gov (NCT00672074).
Beck DE et al. Int J Colorectal Dis. 2014. PMID: 25331030. DOI: 10.1007/s00384-014-2030-8.
All findings above are from published, peer-reviewed sources. None establish approved therapeutic use of CJC-1295 or Ipamorelin outside a clinical-trial setting, and neither compound is licensed for human use in the UK, EU or US. Both are prohibited in competitive sport by WADA.
Stability
Why format matters
Like all peptides, CJC-1295 and Ipamorelin are chemically fragile once dissolved. Hydrolysis and oxidation begin as soon as the peptide enters solution, and continue for as long as it stays that way.
Pre-filled peptide pens are dissolved at the point of manufacture and remain in solution through shipping, customs clearance, warehousing and delivery.
A freeze-dried presentation avoids that. The peptide stays dry and stable until the buyer reconstitutes it.
We cover the format question in full on freeze-dried vs pre-filled.
Frequently asked
Common questions about CJC-1295 and Ipamorelin
What is CJC-1295?
CJC-1295 is a synthetic 30-amino-acid analogue of growth hormone releasing hormone (GHRH). It contains four amino acid substitutions in the standard GHRH sequence that make it more resistant to enzymatic degradation. In the research literature, two forms are commonly discussed: CJC-1295 without DAC (also called Mod GRF 1-29 or Sermorelin variant) has a short half-life; CJC-1295 with DAC (drug affinity complex) has an extended half-life due to a bond with serum albumin that keeps it in circulation for days.
What is Ipamorelin?
Ipamorelin is a synthetic pentapeptide that acts as a selective growth hormone secretagogue — it binds to the ghrelin receptor (GHSR-1a) and stimulates pituitary growth hormone release. In the research literature it has been noted for its selectivity: it does not appear to significantly stimulate release of cortisol, prolactin, or aldosterone at doses that stimulate GH release. It is investigational and not approved as a medicine.
Why are CJC-1295 and Ipamorelin studied together?
Research literature notes that the two peptides act on different receptors involved in growth hormone regulation — CJC-1295 mimics GHRH acting on the GHRH receptor, and Ipamorelin acts on the ghrelin receptor. Studies investigating combined effects of a GHRH analogue with a ghrelin-receptor agonist have reported additive or synergistic GH release in animal and preclinical models. Because researchers commonly investigate this pairing, many suppliers offer them as a paired kit.
What has CJC-1295 research shown?
The original discovery paper by Teichman et al. (J Clin Endocrinol Metab 2006, PMID 16352683) reported that single subcutaneous injections of CJC-1295 in healthy adults increased mean GH concentrations by 2- to 10-fold for six days or more, with elevated IGF-1 concentrations for 9 to 11 days. A separate translational study by Sackmann-Sala et al. (Growth Horm IGF Res 2009) reported that combined administration of a GHRH analogue with the ghrelin-receptor agonist GHRP-6 in aged rats reversed the age-related decline in GH pulse amplitude. All findings are described as observed in the study — CJC-1295 is investigational.
What has Ipamorelin research shown?
Raun et al. (Eur J Endocrinol 1998, PMID 9678525) — the discovery paper for Ipamorelin — reported that in swine models Ipamorelin released growth hormone with a potency comparable to GHRP-6, with no measurable increase in cortisol, ACTH, or prolactin at doses producing maximal GH release. Beck et al. (PLoS One 2014, PMC PMC3934962) reported acute Ipamorelin administration increased GH release in rats without triggering significant increases in cortisol or prolactin. Selectivity is a key characteristic reported in the primary literature.
What is the difference between CJC-1295 with DAC and without DAC?
DAC stands for Drug Affinity Complex — a specific chemical modification (a maleimidopropionic acid attachment) that lets the peptide form a covalent bond with serum albumin. Because albumin has a long half-life in circulation, the DAC-bonded peptide stays in the bloodstream for days rather than minutes. Without DAC (also called Mod GRF 1-29), the peptide is cleared within hours. The two forms have measurably different pharmacokinetic profiles and are studied in distinct research contexts.
Are CJC-1295 and Ipamorelin legal in the UK?
Neither peptide is authorised as a medicine by the MHRA in the UK, the EMA in the EU, or the FDA in the US. Neither can lawfully be sold for human use. Both may be lawfully supplied for laboratory research purposes only. Any seller presenting either as an approved therapy is misrepresenting them.
Are CJC-1295 and Ipamorelin banned in competitive sport?
Yes. Both fall under the World Anti-Doping Agency (WADA) Prohibited List category of “Peptide Hormones, Growth Factors, Related Substances, and Mimetics” — specifically the sub-category of growth hormone releasing factors (GHRHs) and growth hormone secretagogues (GHS). Both are prohibited at all times in competitive sport. Athletes considering any research compound must consult current WADA rules and their national anti-doping organisation directly.
What purity should a research-grade CJC-1295 or Ipamorelin COA show?
Purity of 98% or higher by HPLC is the industry benchmark. Identity should be independently confirmed by mass spectrometry, verifying molecular weight and confirming the compound matches the label. The COA must be produced by a named independent laboratory. See how to read a peptide Certificate of Analysis.
Where can I find the primary research?
CJC-1295: Teichman et al. 2006, J Clin Endocrinol Metab (PMID 16352683 — extended half-life pharmacokinetics). Ipamorelin: Raun et al. 1998, Eur J Endocrinol (PMID 9678525 — original discovery, selective GH release); Beck et al. 2014, PLoS One (PMC3934962 — mechanism and selectivity). All freely accessible via PubMed.
Buying checklist
What to check before buying
- Format. Freeze-dried or pre-filled? Pre-filled has been in solution since the factory.
- A published, batch-specific COA from a named independent laboratory. See how to read one.
- Purity by HPLC. 98%+ is the benchmark. Identity by mass spectrometry.
- Which form. CJC-1295 is supplied in two forms — with and without DAC affinity modification — and the two behave very differently in the body. The COA and product listing should state which.
- Honest framing. A seller making therapeutic claims about an unlicensed compound is telling you something about how they operate.
- Batch traceability. Can you match what you received to a specific test result?
Misconceptions
Common misconceptions
“CJC-1295 and Ipamorelin do the same thing.”They act on different receptors. CJC-1295 is a GHRH-receptor agonist; Ipamorelin is a ghrelin-receptor agonist. Their commercial pairing reflects that difference, not sameness.
“They’re natural, so they must be safe.”Both are synthetic peptides. Ipamorelin is not naturally present in the body. CJC-1295 is a modified GHRH analogue, not native GHRH. Safety in humans has not been established through regulated clinical trials.
“They boost growth hormone naturally.”They act pharmacologically on growth-hormone-axis receptors. “Naturally” is a marketing framing that obscures how the compounds actually work.
“A COA on the website covers everything.”Only if it is batch-specific, recent, independent, and matches the product you are buying.
Our CJC-1295 / Ipamorelin
Freeze-dried, tested, batch-traceable
Supplied freeze-dried, not pre-filled, with a bacteriostatic water pen in the same kit. Independently tested by third-party laboratory, with the Certificate of Analysis published per batch in our COA Library.
Supplied strictly for research use.
Research use only. CJC-1295 and Ipamorelin are investigational compounds and are not licensed for human use in the United Kingdom, the European Union or the United States. Supplied strictly for laboratory research purposes. Not for human consumption. Not intended to diagnose, treat, cure or prevent any disease. Purchasers must be 18 or over.