What it is

CJC-1295 is a synthetic analogue of growth hormone-releasing hormone (GHRH), the hypothalamic signal that tells the pituitary to release growth hormone [1]. The name covers two different molecules. The version studied in the published human trials carries a “drug affinity complex” (DAC) that binds to albumin in the blood after injection, which is what makes it long-acting [2]. A second version without the DAC is also sold under the same name; FDA’s 2024 briefing document notes that the “CJC-1295” used in compounded combinations is referred to as tetra-substituted GRF (1-29), or CJC without DAC [6]. It is not an FDA-approved drug and has no approved indication [4]. Ask your prescriber which form your product is, because the two behave very differently in the body.

How it works

Like natural GHRH, CJC-1295 acts on pituitary cells to increase growth hormone (GH) output, which in turn raises insulin-like growth factor I (IGF-I) [1]. In a two-part study in healthy adults, a single subcutaneous injection of the DAC form raised mean GH 2- to 10-fold for six days or more and IGF-I 1.5- to 3-fold for 9 to 11 days [1]. A second study in healthy young men sampled blood every 20 minutes overnight one week after a single injection and found that GH was still released in pulses: pulse frequency and size were unchanged, but trough GH levels rose about 7.5-fold, overall GH rose 46 percent and IGF-I rose 45 percent [2]. The albumin binding is why the DAC form keeps working for days rather than minutes [2].

What the evidence shows

Human data on CJC-1295 come from small, short studies in healthy volunteers, not from trials in any disease. The main trial was two randomized, placebo-controlled, ascending-dose studies lasting 28 and 49 days in healthy subjects aged 21 to 61, which measured hormone levels rather than clinical outcomes [1]. The second study measured GH pulsatility in healthy 20- to 40-year-old men after one injection [2]. Neither study tested body composition, recovery, sleep or any health outcome. FDA’s summary of the substance states that available clinical data are limited [4]. No published human study of the no-DAC form was found during verification. Claims you may see about fat loss, muscle gain or anti-aging are not supported by these sources.

Regulatory status

CJC-1295 is not FDA-approved [4]. On September 29, 2023 FDA added it to Category 2 of the 503A nominated bulk drug substances list, the category for substances FDA says raise significant safety risks [3]. Its nomination was later withdrawn; FDA now lists it under “bulk drug substances nominated but withdrawn” while still describing its safety concerns [4]. It does not appear in Category 1, 2 or 3 of the list FDA updated on May 14, 2026 [5]. Removal from Category 2 does not place a substance on the 503A bulks list or in Category 1 [8]. State boards act too: the Ohio Board of Pharmacy has taken enforcement action against pharmacies compounding CJC/ipamorelin [7]. Status verified September 24, 2026.

Half-life and what it means for a level curve

The only human pharmacokinetic data are for CJC-1295 with DAC. The estimated half-life in healthy adults after subcutaneous injection was 5.8 to 8.1 days [1]; a later paper cites it as about 8 days [2]. No human half-life has been published for the no-DAC form, and this page does not guess one. STACK has no reference half-life for this compound because the published value applies only to the DAC form and no human value exists for the no-DAC form; you can enter your own estimate after checking with your prescriber which form you have. With any repeating dose, a level reaches about 97 percent of steady state after roughly five half-lives, so a days-long half-life builds up over weeks while a minutes-long one does not build at all. STACK’s curve is an estimate from this published half-life, not a blood level.

Reported side effects

Human safety data are thin. In the main trial, no serious adverse reactions were reported and the authors described the DAC form as relatively well tolerated in healthy adults [1]. FDA’s summary, written for compounding review, says it has identified serious adverse events associated with CJC-1295 including increased heart rate and a systemic vasodilatory reaction, and that compounded products may pose a risk of immunogenicity and peptide-related impurities [4]. Both human studies also reported sustained rises in GH and IGF-I, hormones with effects beyond the study window [1][2]. There is no FDA label listing adverse reactions for this substance. Log anything you notice in STACK and call your prescriber if something concerns you.

Storage and handling

There is no FDA-approved product and therefore no FDA label with storage instructions for CJC-1295 [4]. If your prescriber’s pharmacy dispenses it, the pharmacy’s label governs: follow its instructions on refrigeration, protection from light, the beyond-use date and how long a reconstituted vial may be kept. FDA’s 2024 briefing document describes compounded peptide products of this kind as lyophilized powders for subcutaneous injection, which means they are mixed with a diluent before use [6]. STACK’s reconstitution calculator does the volume arithmetic from the numbers on your vial and pharmacy label; it does not suggest what to take. If a vial looks cloudy or has passed its pharmacy date, ask the pharmacy before using it.

What STACK tracks for it

STACK logs each dose exactly as your prescriber wrote it, in mcg, together with the date, time and injection site. Because the two forms differ so much, STACK asks you to record whether your product is with DAC or without DAC, and only draws an estimated level curve once you enter a half-life estimate for your form. You can also track weight, sleep, injection-site reactions and any side effect, and keep a vial inventory with the pharmacy’s beyond-use date so you know when a vial should be discarded. If your prescriber also prescribes ipamorelin, STACK tracks it as a separate compound on its own page. Nothing in STACK is a recommendation to start, stop or change a dose.

The reference half-life in STACK

STACK ships CJC-1295 without a default half-life: With DAC: 5.8–8.1 days (about 139–194 h). Without DAC: no published human value.. You enter your own estimate before a curve is drawn. Measured in: healthy adults aged 21–61, subcutaneous, CJC-1295 with DAC only.

CJC-1295 (no DAC)

No default

No published human half-life for CJC-1295 without DAC (modified GRF 1-29). Check with your prescriber which form you have and set your own estimate; the with-DAC form is a separate entry. Educational only — not medical or dosing advice.

CJC-1295 with DAC

167 h (7 days)

Reference half-life is the middle of the published 5.8–8.1 day range for CJC-1295 with DAC in healthy adults; editable. Only applies to the DAC form. Educational only — not medical or dosing advice.

“The estimated half-life of CJC-1295 was 5.8-8.1 d.” — 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 (2006). Journal of Clinical Endocrinology & Metabolism 91(3):799–805 · PubMed 16352683. View source

Simulate CJC-1295 with DAC Plan with CJC-1295 with DAC

Estimate only. Modelled from the published half-life you selected and the doses you logged — not a measured blood level. Do not use it to make medication decisions.

Free tools for CJC-1295

Sources

Every URL below was fetched and checked on 2026-09-24. Bracketed numbers in the text link here.

CJC-1295