CJC-1295
A modified growth hormone-releasing peptide with actual human trial data behind it. The DAC vs no-DAC distinction is critical — here's what it means and why most practitioners prefer one over the other.
CJC-1295 is a modified GHRH analogue — essentially an improved version of sermorelin with better stability. It comes in two forms: with DAC (long-acting, sustained GH elevation) and without DAC (short-acting, pulsatile release). Most longevity practitioners prefer the no-DAC version because it mimics your body's natural GH rhythm.
Often used by: Adults seeking GH optimisation (usually combined with ipamorelin), people wanting published human data backing their peptide choice.
Dive deeper into the researchCommon side effects
- Transient flushing or warmth after injection
- Tingling in hands/feet from mild water retention
- Vivid dreams, particularly in first few weeks
What does CJC-1295 do?
CJC-1295 works the same way as sermorelin — it activates the GHRH receptor on your pituitary to trigger growth hormone release. The difference is engineering: four amino acid substitutions make it more stable and longer-lasting than sermorelin.
The DAC distinction matters. "DAC" (Drug Affinity Complex) is a modification that lets the peptide bind to albumin in your blood, extending its half-life from 30 minutes to 6–8 days. Sounds convenient, but the sustained GH elevation blunts your body's natural pulsatile rhythm and increases receptor desensitisation risk. Most longevity practitioners avoid DAC for this reason.
CJC-1295 without DAC (also called "Modified GRF 1-29") produces a single GH pulse per injection — physiologically normal, receptor-friendly, and ideal for combining with ipamorelin before sleep.
Who uses it?
- Combined with ipamorelin — the most common GH optimisation protocol in longevity medicine
- Adults 40+ — restoring age-related GH decline through pulsatile stimulation
- Evidence-minded users — CJC-1295 has a published human RCT, which is rare among research peptides
- Sleep and recovery — pre-sleep dosing amplifies the natural nocturnal GH pulse
What to know before trying
CJC-1295 without DAC (Modified GRF 1-29) is preferred for longevity protocols. It preserves pulsatile GH release and maintains feedback regulation. The DAC version creates sustained, non-physiological GH elevation. Vendors sometimes label no-DAC product simply as "CJC-1295" — always verify.
Inject before sleep: 30–60 minutes before bed, empty stomach. Combined with ipamorelin 100–300 mcg in the same syringe.
Cycle 8–12 weeks on, 4–8 weeks off. Track IGF-1 at weeks 8–10 to assess response.
Naming confusion: If the product description mentions a half-life of "days," it contains DAC. If "minutes," it doesn't. This is the simplest way to verify.
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Get early accessFrequently Asked Questions
CJC-1295 with DAC vs without DAC — which is better?
For longevity and physiological GH optimisation, most practitioners prefer no-DAC. It preserves pulsatile GH release, maintains somatostatin feedback, and avoids receptor desensitisation. DAC produces sustained non-pulsatile elevation that more closely resembles continuous HGH — which peptide protocols are designed to avoid.
How to combine CJC-1295 with ipamorelin?
Use CJC-1295 no-DAC (100–200 mcg) + ipamorelin (100–300 mcg) combined in one insulin syringe. Inject subcutaneously before sleep on an empty stomach. They work through two independent pathways (GHRH and ghrelin receptors) for synergistic GH release.
Does CJC-1295 have human clinical trial data?
Yes — CJC-1295 with DAC was studied in a published randomised controlled trial (Teichman et al., J Clin Endocrinol Metab, 2006) showing dose-dependent IGF-1 increases in healthy adults. This is more human data than most research peptides have.
What are CJC-1295 side effects?
Common: transient flushing after injection, mild tingling from water retention, vivid dreams. At excessive doses or without monitoring: joint swelling, carpal tunnel symptoms, and insulin resistance from supraphysiological IGF-1. Regular IGF-1 monitoring prevents these.
How it works in your body
CJC-1295 activates the same GHRH receptor as sermorelin and natural GHRH, triggering intracellular cAMP signalling in pituitary somatotrophs. The four amino acid modifications improve enzymatic stability — DPP-IV (the enzyme that degrades natural GHRH) can't break it down as quickly, giving it a longer effective window.
When combined with ipamorelin (which activates the ghrelin receptor on the same cells), both cAMP and IP3/DAG signalling cascades fire simultaneously, producing a synergistic GH pulse substantially larger than either compound alone.
The human trial
Teichman et al. (2006) published a randomised, double-blind, placebo-controlled trial in healthy adults showing 3–10 fold increases in mean GH concentration and sustained IGF-1 elevations of 30–40% above baseline lasting up to 28 days after a single injection (DAC version). Generally well-tolerated with no serious adverse events.
What to monitor
- IGF-1 — primary safety and efficacy marker. Baseline and every 3 months.
- Fasting glucose — GH affects insulin sensitivity
- Body composition — DEXA or consistent waist measurement at 3-month intervals
- Sleep quality — weekly subjective tracking
Side effects & safety
CJC-1295's side effects are dose-dependent and manageable with proper monitoring:
- Flushing — warmth or redness shortly after injection. Transient and common.
- Water retention — mild fluid retention felt as tingling in hands/feet or puffiness. Usually resolves within days.
- Vivid dreams — enhanced deep sleep leads to more vivid dream recall. Not harmful.
- Injection site reactions — standard subcutaneous injection reactions: redness, tenderness.
- At supraphysiological IGF-1 levels: Joint swelling, carpal tunnel symptoms, and insulin resistance. These indicate the dose is too high or monitoring is inadequate.
- Fatigue — some users report tiredness during the first week as the body adjusts to altered GH pulsatility.
Who should avoid it: People with active cancer, pregnant or breastfeeding women, those with uncontrolled diabetes or pituitary conditions.
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