Ipamorelin vs CJC-1295: Two Growth Hormone Peptides Compared

Ipamorelin and CJC-1295 both prompt the pituitary gland to release growth hormone, but through different receptors. Ipamorelin is a five-amino-acid ghrelin-receptor agonist that produces a short pulse of growth hormone. CJC-1295 is an engineered version of growth hormone-releasing hormone (GHRH); its original form binds to albumin in the blood and acts for days. Neither is FDA-approved.

The two are often sold together as a single product, on the logic that hitting both receptors adds up. That logic is pharmacologically plausible, but we found no published controlled trial of the combination. Most of what is known about each comes from small hormone studies, animal work and FDA’s compounding reviews.

This page compares the chemistry, the human evidence, safety signals, legal status as of September 2026, and what to look for on a certificate of analysis (COA). It gives no dosing, cycling or usage guidance.

At a glance

Property	Ipamorelin	CJC-1295
Drug class	Growth hormone secretagogue (ghrelin mimetic)	GHRH analogue
Receptor	Ghrelin receptor (GHS-R1a)	GHRH receptor
Structure	Pentapeptide with non-natural amino acids	Modified GHRH(1-29), with or without DAC
Duration in human studies	Half-life about 2 hours; single GH pulse	DAC form: half-life about 6 to 8 days
Human evidence	PK study in healthy men; one negative phase 2 trial	Two small placebo-controlled hormone studies (2006)
FDA approval	Not approved	Not approved
FDA advisory committee	Voted against bulks listing (October 2024)	Voted 0-13 against bulks listing (December 2024)
WADA 2026	Prohibited at all times (S2)	Prohibited at all times (S2)
Canada	Named in Health Canada’s April 2026 advisory	Named in the same advisory
Key COA check	Mass spec identity; watch for modified analogues	Mass spec to confirm DAC or no-DAC form

Two routes to the same hormone: ghrelin mimetic vs GHRH analogue

Growth hormone release from the pituitary is driven mainly by GHRH from the hypothalamus and held back by somatostatin. A second input comes through the ghrelin receptor. Ipamorelin and CJC-1295 each target one of these routes, which is why they are marketed as complementary. Our GHRH glossary entry explains the first of these systems.

Ipamorelin is a pentapeptide (Aib-His-D-2-Nal-D-Phe-Lys-NH2) developed by Novo Nordisk in the 1990s. In rats and pigs it released growth hormone with potency similar to the older peptide GHRP-6, but unlike GHRP-6 and GHRP-2 it did not raise ACTH or cortisol, even at doses far above those needed for growth hormone release.¹ That selectivity is the basis of its reputation, and it comes from animal data.

Because the ghrelin receptor also influences gut movement, ipamorelin was later tested as a treatment for sluggish bowels after surgery rather than as a growth hormone product.³ That history matters: its only sizeable clinical trial had nothing to do with the uses it is now marketed for.

CJC-1295 is a GHRH analogue. The version tested in people carries a Drug Affinity Complex (DAC) that binds permanently to albumin after injection, giving it a half-life of about eight days.⁵ Much of what is sold as “CJC-1295 no DAC” is a different, short-acting molecule better described as modified GRF (1-29), a name used by forensic chemists who have analysed seized products.⁶ The two should not be treated as interchangeable.

What the human studies found and how the effects differ

For ipamorelin, the key human study is a 1999 pharmacokinetic study in healthy men given infusions at five dose levels, eight men per level. Ipamorelin had a terminal half-life of about two hours and produced a single episode of growth hormone release, peaking at roughly 40 minutes and then falling away to negligible levels.²

For CJC-1295, two randomised, placebo-controlled, ascending-dose trials in healthy adults aged 21 to 61 found that a single injection raised mean growth hormone two- to tenfold for six days or more, and IGF-1 1.5- to threefold for nine to 11 days. The estimated half-life was 5.8 to 8.1 days, and after repeated doses IGF-1 stayed above baseline for up to 28 days.⁴ A follow-up study in young men found that the normal pulsing pattern of growth hormone was preserved, but trough levels rose about 7.5-fold.⁵

So the practical difference, on the evidence, is timing: a brief spike with ipamorelin versus a sustained lift in baseline growth hormone and IGF-1 with the DAC form of CJC-1295. What users report beyond that, such as changes in sleep, recovery or body composition, has not been tested in published controlled trials of either peptide in healthy adults.

Evidence quality: small, old and mostly hormone levels

The largest ipamorelin trial was not about growth hormone at all. A phase 2 study gave intravenous ipamorelin or placebo to 114 analysable patients after bowel surgery. It was well tolerated, but there was no significant difference from placebo in the main outcome, time to tolerating a solid meal (median 25.3 versus 32.6 hours, p = 0.15).³

The CJC-1295 trials are from 2005 and 2006, were small, and measured hormone levels rather than outcomes people care about, such as muscle, fat, strength or injury recovery.⁴⁵ A rise in IGF-1 is a surrogate marker, not evidence of benefit.

Question	Ipamorelin	CJC-1295
Raises growth hormone in humans?	Yes, briefly (PK study)	Yes, for days (DAC form)
Randomised trial of a clinical outcome?	One, negative (postoperative ileus)	None published
Body composition or performance trials?	None published	None published
Trials of the combination?	None published	None published
Long-term safety data?	None	None

Neither peptide went on to become an approved medicine, and the published human record largely stops at these early studies. We found no independent replication in larger groups and no information on what happens with use over months or years.

The honest summary is that both molecules do what they were designed to do to hormone levels in short studies. Whether that translates into anything meaningful, and at what long-term cost, has not been studied.

Safety, side effects and drug testing

FDA’s compounding review of ipamorelin raised immunogenicity concerns, noted that its non-natural amino acids complicate characterisation, and cited serious adverse events, including a death, when ipamorelin was given intravenously. For CJC-1295, FDA cited immunogenicity and serious adverse events including increased heart rate and a systemic vasodilatory reaction.⁷

The long-term effects of repeatedly raising growth hormone and IGF-1 with either peptide have not been studied. Health Canada’s 2026 advisory on unauthorised peptides lists hormonal imbalance, blood sugar imbalance and the growth of cancerous tumours among potential risks, along with infections and contamination.¹² Interactions with medicines, and effects in people with diabetes or pituitary conditions, are unstudied.

The claim that ipamorelin spares cortisol is often repeated as a safety point. It rests on animal experiments; the human pharmacokinetic study measured ipamorelin and growth hormone, not cortisol.¹² Treat it as a hypothesis rather than an established human finding.

For athletes, WADA’s 2026 list names ipamorelin among growth hormone secretagogues and CJC-1295 among GHRH analogues under S2. Both are prohibited at all times.¹¹ Forensic chemists have also found glycine-modified versions of ipamorelin and modified GRF (1-29) in seized doping material, which is one reason testing methods keep being updated.⁶

Legal status in September 2026

United States. Neither is an FDA-approved drug. A 503A compounding pharmacy may generally use a bulk substance only if it meets a USP or NF monograph, is a component of an FDA-approved drug, or appears on FDA’s 503A bulks list.¹⁰ Neither peptide meets those conditions.

Both were once in Category 2 of FDA’s interim policy, and their nominations were later withdrawn.⁷ FDA’s Pharmacy Compounding Advisory Committee then voted against adding ipamorelin to the bulks list in October 2024,⁸ and in December 2024 voted 0-13 against every form of CJC-1295 it considered.⁹ Ipamorelin acetate also remains in Category 2 for 503B outsourcing facilities.⁷

Neither was part of FDA’s April 2026 Category 2 changes or the July 2026 advisory meeting that backed BPC-157 and several other peptides, covered in our 503A bulks list explainer. That leaves neither with a pending FDA pathway comparable to the one BPC-157 is now on. State pharmacy boards add their own rules.

UK. Neither is a licensed medicine. Canada. Health Canada’s April 2026 advisory named both CJC-1295 and ipamorelin among unauthorised injectable peptides it had seized.¹²

Research use only sales and what a COA should show

Most ipamorelin and CJC-1295 reaches consumers as research use only products. That label does not make a product legal for human use: Health Canada says this type of labelling does not exempt products from regulatory requirements, and FDA takes the same line in its warning letters.¹² Our guide to what research use only means sets out why.

If you are assessing a product’s paperwork, a useful COA should include:

• HPLC purity with the actual chromatogram.
• Mass spectrometry identity. The DAC and no-DAC forms of CJC-1295 have different molecular masses, so this should settle which one is in the vial. It would also reveal modified analogues of the kind found in seized products.⁶
• Endotoxin results and sterility testing for anything sold in a vial.
• The lot number on the vial, the laboratory’s name, and a recent test date. A blend needs results for each peptide.

Our entries on ipamorelin, CJC-1295 and peptide source verification explain how to check a report against the issuing laboratory.

Frequently asked questions

What is the difference between CJC-1295 with and without DAC?

The DAC version carries a chemical group that binds to albumin, so it lasts for days; its half-life in human studies was about six to eight days.⁴ The no-DAC product is a different, short-acting molecule often called modified GRF (1-29).⁶ The published human trials used the long-acting form, so their results do not describe the no-DAC product.

Which is stronger, ipamorelin or CJC-1295?

They cannot be ranked on current evidence. They act on different receptors, over different timescales, and have never been compared head to head. Ipamorelin produced a short growth hormone pulse in a pharmacokinetic study, while the DAC form of CJC-1295 raised growth hormone and IGF-1 for days.²⁴ Neither has trial data on outcomes such as muscle or recovery.

Why are ipamorelin and CJC-1295 sold together?

Sellers argue that stimulating the ghrelin receptor and the GHRH receptor at once gives a larger growth hormone release. That is a reasonable hypothesis based on how the two systems work, but we found no published controlled human trial of the combination, and FDA’s advisory committee rejected both for compounding in 2024.⁸⁹ We do not give usage guidance.

Does ipamorelin raise cortisol?

In the original rat and pig experiments, ipamorelin released growth hormone without raising ACTH or cortisol, unlike the older peptides GHRP-2 and GHRP-6.¹ That is where its reputation for selectivity comes from. We found no controlled human study confirming the same selectivity with repeated use, so the claim should be read as animal evidence.

Are ipamorelin and CJC-1295 legal in the US?

Neither is FDA-approved, and neither is on the 503A bulks list that lets compounding pharmacies use a substance. FDA’s advisory committee voted against both in 2024.⁸⁹ Products sold online as research use only are not a lawful route for human use, whatever the label says.

Are ipamorelin and CJC-1295 banned in sport?

Yes. WADA’s 2026 Prohibited List names ipamorelin as a growth hormone secretagogue and CJC-1295 as a GHRH analogue under section S2. Both are prohibited in and out of competition.¹¹ Athletes should also know that seized products have contained modified analogues that labels do not disclose.⁶

Sources

1. Raun K, Hansen BS, Johansen NL, Thøgersen H, Madsen K, Ankersen M, Andersen PH. Ipamorelin, the first selective growth hormone secretagogue. Eur J Endocrinol. 1998;139(5):552-561. DOI: 10.1530/eje.0.1390552. PMID: 9849822. pubmed.ncbi.nlm.nih.gov
2. Gobburu JV, Agersø H, Jusko WJ, Ynddal L. Pharmacokinetic-pharmacodynamic modeling of ipamorelin, a growth hormone releasing peptide, in human volunteers. Pharm Res. 1999;16(9):1412-1416. DOI: 10.1023/a:1018955126402. PMID: 10496658. pubmed.ncbi.nlm.nih.gov
3. Beck DE, Sweeney WB, McCarter MD; Ipamorelin 201 Study Group. Prospective, randomized, controlled, proof-of-concept study of the Ghrelin mimetic ipamorelin for the management of postoperative ileus in bowel resection patients. Int J Colorectal Dis. 2014;29(12):1527-1534. DOI: 10.1007/s00384-014-2030-8. PMID: 25331030. pubmed.ncbi.nlm.nih.gov
4. Teichman SL, Neale A, Lawrence B, Gagnon C, Castaigne JP, Frohman LA. Prolonged stimulation of growth hormone (GH) and insulin-like growth factor I secretion by CJC-1295, a long-acting analog of GH-releasing hormone, in healthy adults. J Clin Endocrinol Metab. 2006;91(3):799-805. DOI: 10.1210/jc.2005-1536. PMID: 16352683. pubmed.ncbi.nlm.nih.gov
5. Ionescu M, Frohman LA. Pulsatile secretion of growth hormone (GH) persists during continuous stimulation by CJC-1295, a long-acting GH-releasing hormone analog. J Clin Endocrinol Metab. 2006;91(12):4792-4797. DOI: 10.1210/jc.2006-1702. PMID: 17018654. pubmed.ncbi.nlm.nih.gov
6. Gajda PM, Holm NB, Hoej LJ, Rasmussen BS, Dalsgaard PW, Reitzel LA, Linnet K. Glycine-modified growth hormone secretagogues identified in seized doping material. Drug Test Anal. 2019;11(2):350-354. DOI: 10.1002/dta.2489. PMID: 30136411. pubmed.ncbi.nlm.nih.gov
7. U.S. Food and Drug Administration. Certain Bulk Drug Substances for Use in Compounding that May Present Significant Safety Risks. Page updated 22 April 2026. fda.gov
8. Alliance for Pharmacy Compounding. PCAC votes against four nominated bulk drug substances. 2024. a4pc.org
9. U.S. Food and Drug Administration. Pharmacy Compounding Advisory Committee, 4 December 2024: Final Summary Minutes (CJC-1295, AOD-9604, thymosin alpha-1). fda.gov
10. U.S. Food and Drug Administration. Bulk Drug Substances Used in Compounding Under Section 503A of the FD&C Act. Page updated 14 May 2026. fda.gov
11. World Anti-Doping Agency. The 2026 Prohibited List (S0 Non-approved substances; S2 Peptide hormones, growth factors, related substances and mimetics). wada-ama.org
12. Health Canada. Think twice before injecting peptides bought online: unauthorized products can seriously harm you. Public advisory, 9 April 2026. recalls-rappels.canada.ca

Editorial note: This article is for general information only and is not medical or legal advice. Ipamorelin and CJC-1295 have not been evaluated by the FDA to diagnose, treat, cure or prevent any disease. Laws vary by location and change often, so verify the rules that apply where you are. Always talk to a licensed healthcare provider before use, especially if you are under 21, pregnant or nursing, taking medication, or managing a health condition.