CJC-1295
Also known as: CJC-1295 DAC, CJC-1295 without DAC, Modified GRF 1-29
Long-acting growth hormone releasing hormone analog — sustained GH pulses for muscle growth, fat loss, and recovery.
Growth Hormone Peptides
CJC-1295
Research use only. Not FDA-approved. May affect blood glucose. Monitor IGF-1 levels with medical supervision.
Overview
CJC-1295 is a synthetic analog of Growth Hormone Releasing Hormone (GHRH). The DAC (Drug Affinity Complex) version has an extended half-life of 6–8 days due to its ability to bind albumin, while the non-DAC version (Modified GRF 1-29) has a shorter half-life of ~30 minutes. Both stimulate the pituitary gland to release growth hormone in natural pulsatile patterns.
CJC-1295 is a synthetic analog of Growth Hormone Releasing Hormone (GHRH), the natural peptide produced in the hypothalamus that signals the pituitary gland to produce and secrete growth hormone. Unlike exogenous human growth hormone (HGH), which bypasses the body's own regulatory system, CJC-1295 works within the natural GH axis — it stimulates your pituitary to produce GH in its own natural pulsatile rhythm, preserving the feedback loops that prevent overproduction.
There are two important versions of CJC-1295 with meaningfully different pharmacokinetic profiles. CJC-1295 with DAC (Drug Affinity Complex) features a chemical modification that allows it to bind to serum albumin in the bloodstream, dramatically extending its half-life from approximately 30 minutes to 6–8 days. This makes it suitable for once or twice-weekly injections. CJC-1295 without DAC — often called Modified GRF 1-29 or "Mod GRF" — has the shorter, more physiological half-life and is typically injected 2–3 times daily to mimic natural pulsatile GHRH secretion.
The clinical evidence is substantive: a published Phase I/II trial in healthy adults demonstrated that a single injection of CJC-1295 with DAC produced sustained, dose-dependent increases in GH and IGF-1 concentrations lasting up to 14 days. Mean GH levels increased 2–10 fold and IGF-1 levels increased 1.5–3 fold compared to baseline. These downstream effects on IGF-1 are responsible for many of the practical benefits observed: enhanced muscle protein synthesis, accelerated fat oxidation, improved collagen production, and better sleep architecture due to GH's role in slow-wave sleep.
CJC-1295 is almost universally combined with a GHRP (most commonly Ipamorelin) in clinical peptide protocols. The combination creates a synergistic effect: CJC provides the GHRH signal (which primes the pituitary for GH release) while the GHRP provides a separate ghrelin-receptor signal that amplifies the GH pulse. Together they produce significantly more GH release than either peptide achieves alone — a well-documented pharmacological synergy that has made the CJC-1295/Ipamorelin stack the most commonly prescribed peptide combination in anti-aging and hormone optimization medicine.
Mechanism of Action
CJC-1295 binds to GHRH receptors in the pituitary gland, stimulating growth hormone synthesis and secretion. The DAC version extends activity through covalent albumin binding. This results in increased IGF-1 levels which mediate many of GH's anabolic and lipolytic effects.
Use Cases
- ✓Lean muscle mass development
- ✓Body fat reduction
- ✓Improved sleep quality and recovery
- ✓Anti-aging protocols
- ✓Growth hormone deficiency (under medical supervision)
- ✓Bone density improvement
Research Summary
Clinical studies have demonstrated that CJC-1295 significantly increases plasma GH and IGF-1 concentrations in healthy adults. A Phase I/II trial showed sustained GH elevation for up to 14 days with a single injection of the DAC version. Commonly paired with ipamorelin for synergistic GH release.
Explain It Like I'm 5 Years Old
Your brain sends a special phone call to a gland in your head called the pituitary, saying "hey, release some growth hormone!" Normally that call is very short — over in minutes. CJC-1295 is like a phone call that stays connected for days instead of minutes, so your pituitary keeps getting that signal to release growth hormone much more often. This means your body repairs itself faster, builds more muscle, and burns more fat.
How the Gym Bros Are Using It
Always stacked with Ipamorelin — never run alone. CJC provides the GHRH signal (the gas pedal for GH release) while Ipamorelin provides the GHRP signal (the turbocharger). Run 100–200 mcg of the no-DAC version (Mod GRF 1-29) alongside 200–300 mcg Ipamorelin, injected 30–60 min before bed on an empty stomach. Effects are cumulative: better sleep in week 1, noticeably faster recovery by week 4, real body composition changes (less fat, more lean mass) by weeks 8–12. The DAC version (once or twice a week) is more convenient but less physiologically pulsatile.
Typical Dosing
CJC-1295 DAC: 1–2 mg per week. Modified GRF 1-29: 100–200 mcg 2–3x daily, often combined with ipamorelin.
Administration
Research Chemical
Research use only. Not FDA-approved. May affect blood glucose. Monitor IGF-1 levels with medical supervision.
