CJC-1295

Updated June 29, 2026

CJC-1295 is a synthetic analogue of growth hormone-releasing hormone (GHRH), the hypothalamic peptide that signals the pituitary to release GH. Natural GHRH has a half-life of only 7 minutes in the bloodstream, rapidly degraded by dipeptidyl peptidase-IV (DPP-IV). CJC-1295 was designed to overcome this limitation: a substitution at position 2 (alanine replaced by alanine with a side chain) makes it resistant to DPP-IV cleavage. The DAC (Drug Affinity Complex) version, CJC-1295 with DAC, adds a lysine-maleimide side chain that allows it to covalently bind to circulating albumin, extending its effective half-life to 6 to 8 days. The non-DAC version has a half-life of approximately 30 minutes.

CJC-1295 without DAC (often called ‘modified GRF 1-29’ in the research community) is generally preferred in protocols focused on mimicking physiological GH pulsatility. The DAC version creates a prolonged elevation of GHRH signalling that blunts the pulsatile pattern — convenient for infrequent dosing but less physiologically precise. Without DAC, a single injection produces a GH pulse 15 to 30 minutes later that mirrors the natural pattern, allowing users to work with the body’s own rhythm rather than override it.

The synergy with ipamorelin is well established and is the primary reason these two peptides are almost always discussed together. GHRH (via CJC-1295) and ghrelin agonists (via ipamorelin) act on distinct receptors with additive and sometimes synergistic effects on GH pulse amplitude. Clinical data shows that combining the two produces GH pulses 3 to 6 times larger than either peptide alone, without the adverse hormonal effects of supraphysiological dosing. IGF-1 increases proportionally, supporting the downstream tissue repair, body composition, and recovery benefits attributed to GH axis optimisation.

The benefits of CJC-1295 largely parallel those of the GH axis: improved body composition over months of use (lean mass gains, fat reduction particularly in the abdominal region), better sleep quality, improved skin and hair quality, stronger connective tissue, and enhanced recovery from training and injury. Users in clinical and research contexts typically report measurable IGF-1 increases within 4 to 8 weeks, with body composition changes becoming apparent after 3 to 6 months.

CJC-1295 without DAC is dosed at 100 to 200 mcg per injection, typically one to two times daily, combined with ipamorelin at comparable doses in the same injection. Like all peptides it requires subcutaneous injection — oral bioavailability is negligible. It is sold as a research chemical and is not approved as a prescription drug in most markets. Purity testing from a reputable supplier is essential. This is general information, not medical advice — clinician involvement is recommended for any peptide protocol.