What is CJC-1295 DAC?
CJC-1295 DAC is a growth hormone (GH) secretagogue peptide belonging to the GHRH (Growth Hormone-Releasing Hormone) analog class. It is a modified version of the native 44-amino-acid GHRH, truncated to 30 amino acids and equipped with a patented technology called the Drug Affinity Complex (DAC).
What sets CJC-1295 DAC apart from other secretagogue peptides is precisely this DAC component: a chemical side chain that allows the peptide to bind covalently and reversibly to serum albumin, the most abundant transport protein in blood. This binding protects it from enzymatic degradation and dramatically extends its half-life from the 7 minutes of native GHRH to 6-8 days. The practical result is that a single weekly injection maintains steadily elevated GH levels throughout the entire week.
Unlike CJC-1295 without DAC (Mod GRF 1-29), which requires daily dosing and generates more physiologically mimetic GH pulses, CJC-1295 DAC produces a more continuous and sustained elevation, differentiating it in terms of pharmacological profile and research objectives.
Mechanism of Action
CJC-1295 DAC exerts its effect through activation of GHRH receptors located on somatotroph cells of the anterior pituitary. Binding to these receptors triggers a signaling cascade that culminates in GH synthesis and secretion into the bloodstream.
The DAC mechanism works as follows: the peptide contains a reactive group that forms a stable amide bond with lysine residues on circulating albumin. This bond is reversible, meaning the peptide gradually releases from albumin and can continuously re-activate GHRH receptors over several days.
Physiological effects observed in research studies include:
- GH elevation: Increases of 2 to 10 times above baseline levels, depending on dose and individual characteristics.
- IGF-1 elevation: Rise of 1.5 to 3 times above baseline, sustained for 1-2 weeks after injection.
- Amplification of natural pulsatility: While maintaining higher baseline levels, it preserves the negative feedback of the hypothalamic-pituitary-GH axis.
The combination of CJC-1295 DAC with a ghrelin receptor agonist such as GHRP-2 or Ipamorelin has demonstrated significant synergy in research models, as both classes act on complementary GH stimulation pathways.
Reported Protocol
Standard reported reconstitution: 2 mg vial + 1.0 mL bacteriostatic water, yielding a 2000 mcg/mL (2 mg/mL) solution. Each 0.1 mL contains 200 mcg.
| Weeks | Reported Dose | Frequency |
|---|---|---|
| 1–4 | 1000 mcg (0.5 mL) | Once/week SC |
| 5–12 | 1000–2000 mcg (0.5–1.0 mL) | Once/week SC |
Subcutaneous injection is typically reported in the abdominal area or upper thigh. Given the 6-8 day half-life, the chosen day of the week should remain consistent to avoid accumulation or troughs.
Key difference from CJC-1295 without DAC:
- With DAC: weekly dosing, sustained and more stable GH levels throughout the week.
- Without DAC (Mod GRF 1-29): daily dosing, more physiological pulsatile GH peaks, ~30-minute half-life.
The choice between the two depends on the research protocol’s objective. DAC is more logistically convenient; without DAC more faithfully mimics natural secretion.
Reported Side Effects
Adverse effects observed in research models and reported in literature include:
- Water retention: Common in the first few weeks, especially at higher doses. Manifests as mild bloating or peripheral edema.
- Numbness or tingling: Primarily in hands and wrists, related to elevated GH and IGF-1 (similar to carpal tunnel syndrome at high doses).
- Fatigue or drowsiness: Reported post-injection, especially during the first weeks.
- Headache: Transient, generally in the first 24-48 hours post-injection.
- Mild hypoglycemia: In contexts of fasting or intense exercise combined with elevated GH levels.
- Lipohypertrophy: With prolonged use at the same injection site.
Unlike ghrelin agonists (GHRPs), CJC-1295 DAC has no significant effects on appetite or cortisol levels.
Storage
- Lyophilized (powder): Store at -20°C, protected from light. Stable until indicated expiration date.
- Reconstituted: Once prepared with bacteriostatic water, store at 2-8°C (conventional refrigerator). Stable for up to 4 weeks.
- Never freeze the reconstituted solution.
- Use an insulin syringe (100 units = 1 mL) for dosing precision.
This content is for educational purposes only. Not medical advice. Always consult a healthcare professional before starting any research protocol.
Reported protocol (research reference)
| Vial sizes | 2 mg |
|---|---|
| Reported dose | Research literature reports: 1000-2000 mcg (0.5-1.0 mL) subcutaneous once per week. Standard reconstitution: 2 mg vial with 1.0 mL bacteriostatic water = 2000 mcg/mL. |
| Half-life | 6-8 days due to the Drug Affinity Complex (DAC) enabling reversible covalent binding to serum albumin. |
| FDA status | Not FDA approved |