What is CJC-1295 No DAC (Mod GRF 1-29)?
CJC-1295 No DAC, also known as Modified GRF 1-29 or simply Mod GRF 1-29, is a synthetic analog of GHRH (Growth Hormone-Releasing Hormone) designed to mimic and improve upon the action of endogenous GHRH. Unlike its Drug Affinity Complex (DAC) variant, this version does not bind to serum albumin, so its half-life is much shorter — approximately 30 minutes — and it generates GH pulses that more closely resemble the natural physiological pattern.
The peptide consists of 29 amino acids corresponding to the first 29 residues of native GHRH (hence the name GRF 1-29), with four strategic substitutions at positions 2, 8, 15, and 27. These modifications significantly increase its resistance to plasma peptidases — primarily DPP-IV — without compromising biological activity or selectivity for the GHRH receptor.
The result is a peptide that acts rapidly and in a pulsatile fashion, stimulating the anterior pituitary to release a burst of GH similar to what occurs naturally during deep sleep or intense exercise. This characteristic makes it the ideal partner in the classic stack: CJC-1295 No DAC + Ipamorelin, considered by many researchers to be the most physiologically sound combination among GH secretagogues.
Mechanism of Action
CJC-1295 No DAC activates GHRH receptors (GHRH-R) expressed on somatotroph cells of the anterior pituitary. This receptor-ligand binding activates adenylate cyclase, raises intracellular cAMP, and triggers the release of stored GH. At the same time, it competitively inhibits the action of somatostatin, the primary physiological inhibitor of GH secretion.
The four amino acid substitutions distinguishing it from native GHRH serve specific functions:
- Position 2 (Ala→D-Ala): Blocks the DPP-IV cleavage site, the plasma enzyme that destroys native GHRH within seconds.
- Position 8 (Gly→Aib): Increases conformational rigidity and receptor binding affinity.
- Position 15 (Gly→Glu): Improves solubility and stability in aqueous solution.
- Position 27 (Met→Nle): Prevents methionine oxidation, increasing storage stability.
The result is a peptide that generates short-duration but high-amplitude GH pulses, preserving the negative feedback of the hypothalamic-pituitary-GH axis. This pulsatile pattern is relevant because GH receptors in target tissues respond better to intermittent peaks than to chronically elevated levels.
Reported Protocol
Standard reconstitution: 5 mg vial + 3.0 mL bacteriostatic water = 1.67 mg/mL (1670 mcg/mL). Each 0.1 mL contains approximately 167 mcg.
| Weeks | Reported Dose | Frequency |
|---|---|---|
| 1–2 | 100 mcg | 1×/day SC, at bedtime |
| 3–4 | 150 mcg | 1×/day SC, at bedtime |
| 5–6 | 200 mcg | 1×/day SC, at bedtime |
| 7–12 | 250–300 mcg | 1×/day SC, at bedtime |
Critical timing: given the ~30-minute half-life, injection timing largely determines efficacy. Research protocols recommend fasted administration (minimum 2 hours without carbohydrates or protein), as plasma insulin and amino acids can attenuate the GH response.
Classic stack with Ipamorelin: the CJC-1295 No DAC + Ipamorelin combination represents the most studied GHRH+GHRP synergy. CJC acts on GHRH receptors and Ipamorelin acts on ghrelin receptors (GHS-R1a), and both pathways are additive for GH secretion. The commonly reported ratio is 1:1 in micrograms, injected simultaneously.
Reported Side Effects
- Facial flushing: A sensation of warmth or transient facial redness reported minutes after injection. It is benign and resolves within 15-30 minutes.
- Mild dizziness: Especially if the injection is performed standing; administering while lying down is recommended.
- Reactive hypoglycemia: In prolonged fasting, GH stimulation can induce lipid mobilization that metabolically competes with glucose.
- Mild water retention: Lower than reported with CJC-1295 DAC due to more transient GH levels.
- Extremity numbness: At higher doses (>300 mcg/day), related to IGF-1 elevation.
- Local irritation: At the injection site, especially with continued use in the same area.
Unlike GHRPs such as GHRP-6, CJC-1295 No DAC does not increase appetite, does not significantly raise cortisol, and does not stimulate prolactin release.
Storage
- Lyophilized (powder): Store at 2-8°C. Stable until indicated expiration date, protected from light and moisture.
- Reconstituted: Store at 2-8°C. Stable for 1-2 weeks (shorter shelf life than reconstituted CJC-1295 DAC).
- Do not freeze the reconstituted solution.
- Rotate injection sites to prevent lipohypertrophy.
- Use 0.3-1 mL insulin syringe for precise dosing.
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 | 5 mg |
|---|---|
| Reported dose | Research literature reports: escalation from 100 mcg (weeks 1-2) to 250-300 mcg (weeks 7-12), subcutaneous once daily at bedtime on an empty stomach. Reconstitution: 5 mg + 3.0 mL bacteriostatic water = 1.67 mg/mL. |
| Half-life | Approximately 30 minutes. Short half-life generates physiologically mimetic GH pulses. Injection timing is critical. |
| FDA status | Not FDA approved |