CJC-1295 and ipamorelin are the two peptides most often named together on growth-hormone protocol pages, and the reason is that they are not alike. CJC-1295 is a lengthened-life version of the hormone that tells the pituitary to release growth hormone; ipamorelin is a small synthetic peptide that reaches the same pituitary cells through a second door, the ghrelin receptor. One lasts days, the other hours. This page sets out each one's dose record (read 2026-10-05) and the syringe arithmetic. It compares; it recommends neither.
The single-compound records are on the CJC-1295 and ipamorelin dosage pages. The two in one vial are worked on CJC-1295 ipamorelin dosage, and the stack itself is described on this site's CJC-1295 and ipamorelin guide.
Side by side
| CJC-1295 | Ipamorelin | |
|---|---|---|
| What it is | GRF(1-29) with four substitutions; the DAC form adds an albumin-binding group | Pentapeptide, Aib-His-D-2-Nal-D-Phe-Lys-NH2 |
| Receptor | GHRH receptor | Ghrelin (GH secretagogue) receptor |
| Molecular weight | 3,647.2 (DAC form) | 711.9 |
| First described | Jetté et al. 2005, Montreal | Raun et al. 1998, Novo Nordisk |
| Human route studied | Subcutaneous, healthy adults (DAC form only) | Intravenous, healthy men and surgical patients |
| Half-life | 5.8–8.1 days (DAC); not published (no DAC) | 2 hours |
| Registry, 2026-10-05 | 1 record, terminated | 3 records, all intravenous |
| Label | None | None |
"CJC-1295" covers two molecules. The one in both human studies carries the Drug Affinity Complex; the one usually sold beside ipamorelin is the no-DAC form, also called Mod GRF 1-29, which has no human study of its own. The difference is set out on CJC-1295 DAC vs no DAC.
One peak against six days
The two human pharmacology studies describe opposite shapes of growth-hormone release:
| Ipamorelin (Gobburu et al. 1999) | CJC-1295 with DAC (Teichman et al. 2006) | |
|---|---|---|
| People | 8 healthy men per dose level, 5 levels | Healthy adults aged 21–61, two ascending-dose trials |
| Dose and route | 4.21–140.45 nmol/kg IV over 15 minutes | Single subcutaneous doses, then 2–3 weekly or biweekly doses |
| GH response | One episode, peak at 0.67 hours, back to negligible | Mean GH up 2- to 10-fold for 6 days or more |
| IGF-I | not reported in the abstract | Up 1.5- to 3-fold for 9–11 days; above baseline up to 28 days after repeated doses |
A third study adds what the continuous signal does: one week after 60 or 90 mcg/kg of CJC-1295 with DAC, growth-hormone pulses kept their frequency and size, but trough GH was 7.5 times higher and IGF-I 45% higher (Ionescu and Frohman 2006). Ipamorelin, by contrast, produces a pulse and is cleared. The no-DAC form sold in blends is, in principle, a short-acting molecule like ipamorelin — but its timing in people has not been measured.
The two also differ in what else they release, on the evidence available. Raun's 1998 profiling in pigs found that GHRP-6 and GHRP-2 raised ACTH and cortisol while ipamorelin did not, even at more than 200 times its half-maximal GH dose, giving it "a selectivity for GH release similar to that displayed by GHRH". That is the property that made ipamorelin notable, and it was shown in animals; no human study of ipamorelin has measured cortisol.
Per kilogram, per microgram, per molecule
| Figure | CJC-1295 with DAC | Ipamorelin |
|---|---|---|
| Human study dose | 30–90 mcg/kg, subcutaneous | about 3–100 mcg/kg, IV (4.21–140.45 nmol/kg); 0.03 mg/kg IV twice daily after surgery |
| At 70 kg | 2.1–6.3 mg per injection | about 0.2–7 mg per infusion; 2.1 mg twice daily |
| Vendor figure (this site's pages, 2026-09-18) | 1–2 mg a week (no DAC: 100–300 mcg, 1–3 times a day) | 100–300 mcg, 1–3 times a day |
| 300 mcg in molecules | about 82 nmol | about 421 nmol |
The per-kilogram conversions and molecule counts are arithmetic by this site from the published doses and PubChem weights; the surgical regimen is the ileus trial recorded on the ipamorelin page. Two things follow. Equal microgram figures — the "100 mcg of each" on many blend pages — put about five ipamorelin molecules beside every CJC-1295 molecule. And neither vendor range comes from a human study: ipamorelin's studied doses were intravenous and mostly larger, and CJC-1295's studied form was the DAC molecule at milligram amounts.
The arithmetic per vial
Units on a U-100 syringe = mcg ÷ concentration in mcg/mL × 100. Both are sold as 5 mg and 10 mg powders.
| Amount | 2.5 mg/mL (5 mg + 2 mL) | 3.33 mg/mL (10 mg + 3 mL) | 5 mg/mL (10 mg + 2 mL) |
|---|---|---|---|
| 100 mcg | 4 units | 3 units | 2 units |
| 200 mcg | 8 units | 6 units | 4 units |
| 300 mcg | 12 units | 9 units | 6 units |
| 1 mg (CJC-1295 DAC) | 40 units | 30 units | 20 units |
| 2 mg (CJC-1295 DAC) | 80 units | 60 units | 40 units |
The reading is the same for either peptide at the same concentration; the molecule count and the length of action are not. In a single vial holding both, every draw carries the two in the fill ratio, which is worked on the blend page. The calculator's CJC-1295, ipamorelin and CJC-1295 ipamorelin settings handle any vial and volume.
What is not established
No trial compares CJC-1295 with ipamorelin or gives them together. CJC-1295's patient trial (NCT00267527, people with HIV and visceral obesity) was terminated without results; ipamorelin's largest trial gave it intravenously after bowel resection and did not reach significance on its main outcome (as recorded on the ipamorelin page). Neither has a subcutaneous human dose study; the no-DAC form has no human data at all. Research vials under either name have no data of their own. The compounds are covered in Medibact's CJC-1295 guide and ipamorelin guide. Nothing on this page is an instruction; dose and product belong with a clinician.
Sources and dates
Opened 2026-10-05: PubMed abstracts 15817669 (Jetté et al., Endocrinology 2005), 9849822 (Raun et al., Eur J Endocrinol 1998), 10496658 (Gobburu et al., Pharm Res 1999), 16352683 (Teichman et al., JCEM 2006) and 17018654 (Ionescu and Frohman, JCEM 2006); PubChem record for ipamorelin (CID 9831659); ClinicalTrials.gov intervention searches for CJC-1295, ipamorelin and both together. The CJC-1295 DAC molecular weight, the ileus-trial regimen and the vendor figures are as recorded on this site's CJC-1295, DAC vs no-DAC and ipamorelin pages (2026-09-18 and 2026-09-27). Per-kilogram totals, molecule counts and units are arithmetic by this site. Corrections go to the contact page.