CJC-1295 dosing splits on one detail most sales pages leave out. The version with DAC lasts days and is dosed weekly. The version without it clears in hours and is dosed like sermorelin. Same name, opposite schedules.
CJC-1295 has no dose that comes from an outcome trial, because none was ever run for the reasons people buy it. What exists is human pharmacokinetic data on how the peptide behaves, and that data sets the schedule cleanly. The one fact that governs everything is which version is in the vial. CJC-1295 with DAC lasts for days and is dosed weekly. CJC-1295 without DAC clears in hours and is dosed like sermorelin. Get that wrong and every other number is wrong with it.
- CJC-1295 with DAC has an estimated half-life of 5.8 to 8.1 days, which is why it is dosed weekly rather than nightly [1]
- A single dose raised plasma GH 2 to 10-fold for 6 or more days and IGF-1 1.5 to 3-fold for 9 to 11 days [1]
- Weekly dosing kept mean IGF-1 above baseline for up to 28 days [1]
- CJC-1295 without DAC clears in hours and is dosed several times a week, closer to sermorelin
- No CJC-1295 dose is trial-established for body composition; any protocol is physician-determined and off-label
- A baseline IGF-1 before the first injection and a retest at about 90 days are what make a dose measurable [1]
Which Version You Have Decides the Schedule
DAC stands for Drug Affinity Complex, an added group that binds the peptide to serum albumin in the bloodstream [3]. That tether is the whole reason the two products behave differently. It shields the peptide from the enzymes that clear ordinary GHRH within minutes, stretching its action from minutes to days.
CJC-1295 with DAC is the version with human data. It carries the albumin group, has an estimated half-life of 5.8 to 8.1 days, and is dosed weekly or twice weekly [1]. CJC-1295 without DAC lacks that group, clears in a matter of hours, and is functionally closer to sermorelin. It is often sold as Mod GRF 1-29, which is vendor labeling rather than an established name. If a program will not say which form it dispenses, that is the first question to ask, because the injection schedule depends on the answer.
What the Human Dosing Data Shows
The schedule for the DAC version rests on two studies in healthy adults. A single subcutaneous dose produced dose-dependent increases in mean plasma GH of 2 to 10-fold that lasted 6 days or more, and increases in IGF-1 of 1.5 to 3-fold that lasted 9 to 11 days [1]. With repeated weekly dosing, mean IGF-1 stayed above baseline for up to 28 days [1]. A peptide that acts for that long does not need a nightly injection.
What those studies did not measure matters as much as what they did. Neither tracked fat, lean mass, strength, or any outcome a person buys CJC-1295 for. There is no published trial of the peptide for body composition or aging at any dose. The dosing guidance is about how to give it safely, not proof of what a given dose will accomplish.
Why Weekly, Not Nightly
Sermorelin is injected every night because it clears in roughly 4 minutes and mirrors the natural nocturnal GH pulse [4]. CJC-1295 with DAC is the opposite design. Its multi-day half-life produces a sustained rise in baseline GH rather than a sharp nightly pulse [1]. Dosing it weekly matches the pharmacology. Dosing it nightly would stack a long-acting drug on top of itself.
One point often misstated is that this sustained elevation flattens natural GH pulses. The study built to test that found the opposite. One week after a dose, GH pulse frequency and size were unchanged while basal GH rose 7.5-fold [2]. Pulses continue at their normal rhythm. What rises is the trough between them. Whether a chronically higher baseline matters over years has not been studied in humans, which is a reason to keep the dose no higher than the labs require.
| CJC-1295 with DAC | CJC-1295 without DAC | |
|---|---|---|
| Albumin-binding group | Present | Absent |
| Half-life | 5.8 to 8.1 days [1] | Hours, closer to sermorelin |
| Dosing frequency | Weekly or twice weekly [1] | Several times per week |
| Human dosing data | Two healthy-adult studies [1][2] | None controlled |
| Injection pattern | Sustained background elevation | Short repeated exposure |
The Dose Itself Is Set From Your Labs
The specific milligram figure belongs to a prescribing physician, set off-label because no CJC-1295 product has an approved label to follow. What makes any figure meaningful is the number it is measured against. A baseline IGF-1 is drawn before the first injection, and without it there is no way to tell whether a dose is doing anything or pushing IGF-1 above the age-adjusted range.
IGF-1 is retested at about 90 days, the point where the response is expected to plateau [1]. A result inside the age-adjusted reference range with symptom improvement supports holding the dose. A result above the range is a reason to lower it, not to continue. This is why a dosing chart printed on a sales page is close to meaningless. It cannot see your starting number or your retest.
The Safety Ceiling and the Red Flags
The ceiling on CJC-1295 is set by IGF-1 and by symptoms, not by how much the vial holds. Water retention, joint stiffness, and carpal-tunnel-type tingling are the familiar signs of pushing GH activity too high, and they ease when the dose comes down. They are a signal to retest, not to push through.
The regulatory signals belong in the dosing decision. FDA states it has identified serious adverse events for CJC-1295, including increased heart rate and systemic vasodilatory reaction, and describes available clinical data as limited [5]. Its only registered patient trial, a Phase 2 study in HIV-associated visceral obesity, is recorded as terminated in 2006 [6]. CJC-1295 is also named on the 2026 WADA Prohibited List, prohibited at all times in and out of competition [7].
A program that sets a CJC-1295 dose without drawing a baseline IGF-1, or that will not say whether it dispenses the DAC or no-DAC form, has skipped the two things a real dosing decision depends on. A fixed dose handed out at checkout, identical for every patient, is a marketing number, not a clinical one.
The Honest Verdict
CJC-1295 dosing is simpler than the charts make it look, and less certain. The schedule follows the half-life: weekly for the DAC version, several times a week for the one without it. The amount is physician-determined and titrated against IGF-1, because no trial has established a dose for the outcomes people want.
If you pursue it, the discipline is the same as for any GH-axis therapy. Confirm which form a licensed prescriber is dispensing. Draw a baseline IGF-1 first. Retest at 90 days and treat a result above the age-adjusted range as a reason to lower the dose. A dose built from your labs is the only one worth following.
CJC-1295 raises IGF-1 for days at a time, which makes a starting number and a 90-day retest more useful, not less. SystemLabs tests IGF-1 before prescribing and formulates CJC-1295 on clinical indication, so the dose and the schedule are built from your labs rather than a fixed chart.
Frequently Asked Questions
What is the correct dose of CJC-1295?
There is no trial-established dose of CJC-1295 for body composition or aging, because the two published human studies measured only GH and IGF-1, not those outcomes [1]. Any specific protocol is physician-determined and off-label, since no CJC-1295 product has an approved label. A dose worth following is set by a prescriber from a baseline IGF-1, not from a vendor chart.
How often should you inject CJC-1295?
It depends on which version is in the vial. CJC-1295 with DAC has an estimated half-life of 5.8 to 8.1 days and is dosed weekly or twice weekly [1]. The version without DAC clears in hours and is dosed several times a week, closer to sermorelin. Confirm the form before setting a schedule, because the two run on completely different clocks.
How long does one dose of CJC-1295 last?
For the DAC version, longer than the half-life alone suggests. A single dose raised plasma GH 2 to 10-fold for 6 or more days and IGF-1 for 9 to 11 days, and weekly dosing kept IGF-1 above baseline for up to 28 days [1]. That sustained action is the reason it is dosed weekly rather than nightly.
Do you need labs to dose CJC-1295?
Yes. A responsible protocol starts from a baseline IGF-1 drawn before the first injection, then retests at about 90 days to see whether the dose moved the number into the age-adjusted range [1]. A program that sets a dose without that baseline has skipped the one step that makes the dose measurable.
Is a higher CJC-1295 dose better?
No. The ceiling is set by IGF-1 and by symptoms, not by milligrams. An IGF-1 above the age-adjusted range at the 90-day retest is a reason to lower the dose, and water retention, joint stiffness, or carpal-tunnel-type tingling are signs of too much GH activity that ease when the dose comes down. FDA has also identified serious adverse events for CJC-1295, including increased heart rate and systemic vasodilatory reaction [5].
Can you dose CJC-1295 without ipamorelin?
Yes, though it is usually stacked with ipamorelin because the two act on different receptors and together produce more GH than either alone. Run on its own, CJC-1295 is still dosed on its half-life, weekly for the DAC version [1]. Adding ipamorelin does not change the CJC-1295 schedule; the two simply run on separate clocks.
References
- 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 Journal of Clinical Endocrinology & Metabolism, 2006. PMID: 16352683. https://pubmed.ncbi.nlm.nih.gov/16352683/
- Pulsatile secretion of growth hormone (GH) persists during continuous stimulation by CJC-1295, a long-acting GH-releasing hormone analog Journal of Clinical Endocrinology & Metabolism, 2006. PMID: 17018654. https://pubmed.ncbi.nlm.nih.gov/17018654/
- Human growth hormone-releasing factor (hGRF)1-29-albumin bioconjugates activate the GRF receptor on the anterior pituitary in rats: identification of CJC-1295 as a long-lasting GRF analog Endocrinology, 2005. PMID: 15817669. https://pubmed.ncbi.nlm.nih.gov/15817669/
- Incorporation of D-Ala2 in growth hormone-releasing hormone-(1-29)-NH2 increases the half-life and decreases metabolic clearance in normal men Journal of Clinical Endocrinology & Metabolism, 1994. PMID: 7962295. https://pubmed.ncbi.nlm.nih.gov/7962295/
- Certain bulk drug substances for use in compounding that may present significant safety risks FDA.gov, Human Drug Compounding, 2026. Content current as of 04/22/2026. https://www.fda.gov/drugs/human-drug-compounding/certain-bulk-drug-substances-use-compounding-may-present-significant-safety-risks
- A multicenter, randomized, placebo-controlled, double-blind, phase 2 study to evaluate the efficacy and safety of CJC-1295 administered for 12 weeks in HIV infected patients with HIV associated visceral obesity ClinicalTrials.gov, 2006. NCT00267527, terminated. https://clinicaltrials.gov/study/NCT00267527
- The 2026 Prohibited List: International Standard, section S2.2.4 growth hormone releasing factors World Anti-Doping Agency, 2026. WADA 2026 Prohibited List. https://www.wada-ama.org/en/resources/2026-prohibited-list
