What is CJC-1295?
CJC-1295 is a synthetic analog of growth hormone releasing hormone (GHRH), specifically a modified version of the first 29 amino acids of GHRH (GRF 1-29) with four amino acid substitutions that dramatically improve its stability and half-life. The modifications replace positions 2, 8, 15, and 27 with D-alanine, glutamine, alanine, and leucine respectively, increasing resistance to enzymatic degradation from the native peptide's 7-minute half-life to approximately 30 minutes for the base compound.
CJC-1295 exists in two distinct forms. The version without DAC (also called Modified GRF 1-29 or Mod GRF) has a half-life of about 30 minutes and produces pulsatile GH release that more closely mimics natural physiology. The version with DAC (Drug Affinity Complex) incorporates a maleimidopropionic acid-lysine linker that binds covalently to albumin in vivo, extending the half-life to 6–8 days and producing sustained, elevated baseline GH levels rather than discrete pulses.
Clinical research on CJC-1295 with DAC demonstrated dose-dependent increases in GH and IGF-1. A Phase 2 study showed that a single 60 mcg/kg injection produced a 2–10 fold increase in GH levels sustained for 6 days, with IGF-1 elevations of 1.5–3 fold lasting up to 14 days [1]. The no-DAC version is preferred in research protocols that aim to preserve the natural pulsatile pattern of GH release, particularly when combined with a GHRP like Ipamorelin for synergistic effect.
Mechanism of Action
CJC-1295 stimulates growth hormone release through direct activation of the GHRH receptor on pituitary somatotrophs:
GHRH Receptor Activation
CJC-1295 binds to the GHRH receptor (GHRHR), a G-protein coupled receptor on anterior pituitary somatotroph cells. This activates adenylyl cyclase, increasing intracellular cAMP, which triggers growth hormone synthesis and secretion. The modified amino acid sequence provides resistance to dipeptidyl peptidase IV (DPP-IV) cleavage, the primary enzyme responsible for degrading native GHRH [1].
Pulsatile vs. Sustained GH Release
The no-DAC variant produces discrete GH pulses lasting 2–3 hours, preserving the body's natural circadian GH rhythm. This pulsatile pattern is considered physiologically superior because continuous GH exposure can lead to receptor desensitization and is associated with the side effects seen in exogenous GH administration. The DAC variant, by contrast, maintains elevated baseline GH levels for 6–8 days, overriding the natural pulse pattern [2].
IGF-1 Axis Stimulation
Both variants increase circulating IGF-1 through hepatic GH receptor activation. IGF-1 mediates many of GH's anabolic effects, including protein synthesis, muscle growth, and bone remodeling. The DAC variant produces more sustained IGF-1 elevation (up to 14 days after a single injection), while the no-DAC version produces transient IGF-1 increases that follow the GH pulse pattern.
Synergy with GH Secretagogues
CJC-1295 (no DAC) and GH secretagogues like Ipamorelin work through different receptors on the same pituitary cells — GHRH receptor and ghrelin receptor (GHS-R) respectively. Co-administration produces synergistic GH release that exceeds the sum of either peptide alone. This is the basis for the widely used CJC-1295/Ipamorelin combination.
Dosing Protocol
Dosing differs significantly between the DAC and no-DAC variants. Timing relative to food intake is critical for both.
| Variant | Dose | Frequency | Duration | Notes |
|---|---|---|---|---|
| Without DAC (Mod GRF) | 100 mcg | 2–3x daily | 8–12 weeks | Pre-sleep + post-exercise on empty stomach |
| With DAC | 2 mg | Once weekly | 8–12 weeks | Sustained GH elevation; simpler protocol |
| Mod GRF + Ipamorelin | 100 mcg each | 2–3x daily together | 8–12 weeks | Most popular research combination |
- Always inject on an empty stomach. Food, especially fats and carbohydrates, blunts the GH response.
- Wait at least 20–30 minutes before eating after injection.
- Optimal timing windows: immediately before sleep, upon waking (fasted), and post-exercise.
- The pre-sleep injection capitalizes on the natural nocturnal GH pulse. This is considered the single most important dose.
- Cycle 8–12 weeks on, 4 weeks off to prevent receptor desensitization.
Reconstitution Guide
Reconstitute lyophilized CJC-1295 with bacteriostatic water. The peptide dissolves readily. Do not shake.
- Remove the plastic cap from the CJC-1295 vial and wipe the rubber stopper with an alcohol swab. Allow to dry.
- Draw the appropriate volume of bacteriostatic water into a sterile syringe (see concentrations below).
- Insert the needle through the rubber stopper at a slight angle. Inject the water slowly against the inner wall of the vial — do not spray directly onto the peptide powder.
- Allow the vial to sit for 1–2 minutes. Gently roll the vial between your palms if needed. Do not shake or vortex.
- The solution should be completely clear and colorless. Discard if you observe any cloudiness, particulate matter, or discoloration.
10 mg vial (no DAC) + 2 mL BAC water: Concentration = 5,000 mcg/mL. For 100 mcg, draw 2 units (0.02 mL). Use a 0.3 mL insulin syringe for accuracy.
5 mg vial (with DAC) + 2.5 mL BAC water: Concentration = 2 mg/mL. For 2 mg, draw 100 units (1.0 mL).
- 3 vials CJC-1295 no DAC (10 mg each) — provides 30 mg total, covers 252 doses of 100 mcg with margin
- 2 vials bacteriostatic water (30 mL each)
- 252 insulin syringes (0.3 mL, 31 gauge for accuracy at small volumes)
- Alcohol prep pads
Injection Technique
CJC-1295 is administered via subcutaneous (SubQ) injection. Injection site does not affect efficacy.
- Clean the injection site with an alcohol swab and allow it to air dry completely (approximately 30 seconds). Common sites: lower abdomen (2 inches from the navel), upper thigh, or upper arm.
- Draw the dose. Insert the needle into the vial through the rubber stopper. Invert the vial and draw the calculated number of units slowly. Tap the syringe to move any air bubbles to the top, then push them out gently.
- Pinch the skin at the injection site to create a fold of subcutaneous tissue. Insert the needle at a 45-degree angle in a quick, smooth motion. Release the skin fold.
- Inject slowly. Depress the plunger steadily over 5–10 seconds. Withdraw the needle at the same angle it was inserted. Apply gentle pressure with a clean swab if needed.
Rotate injection sites to prevent lipodystrophy (localized fat tissue changes). For abdominal injections, use a clock pattern around the navel. CJC-1295 (no DAC) injection volumes are very small (0.02 mL), making injections quick and virtually painless. Allow at least 1 inch between injection sites.
Storage & Stability
CJC-1295 stability varies between the two variants. The DAC version is somewhat more stable after reconstitution due to its albumin-binding properties.
- Keep vials upright and away from direct light.
- If condensation forms on a cold vial, allow it to reach room temperature before opening to prevent moisture contamination.
- Never re-freeze a reconstituted vial. Discard if left at room temperature for more than 4 hours.
- Label reconstituted vials with the date to track the use window.
Side Effects & Considerations
CJC-1295 side effects are primarily related to the downstream effects of elevated growth hormone levels.
Commonly Reported
- Water retention and bloating — particularly during the first 1–2 weeks of use. Usually subsides as the body adjusts.
- Tingling or numbness in extremities — carpal tunnel-like symptoms from GH elevation. More common at higher doses.
- Increased hunger — especially within 30 minutes of injection. This is a direct GHRH effect on appetite centers.
- Headache — usually transient, resolves with continued use.
- Flushing or warmth at injection site.
Variant-Specific Considerations
- The DAC variant may produce more persistent side effects (water retention, paresthesias) due to sustained GH elevation over 6–8 days.
- The no-DAC version produces transient side effects that resolve within hours of the GH pulse subsiding.
- The no-DAC version preserves natural GH pulsatility; the DAC version overrides it, which may affect sleep-related GH secretion patterns.
- Timing matters: inject on an empty stomach. Food (especially fats and carbohydrates) blunts the GH release response.
CJC-1295 is classified as a research peptide. It is not FDA-approved for any clinical indication. All information presented here reflects published research and should not be construed as medical advice or a treatment recommendation.
Stacking Protocols
CJC-1295 (no DAC) is most commonly used in combination with Ipamorelin. This is one of the most well-established peptide stacks in the research community.
CJC-1295 + Ipamorelin (GH Optimization Stack)
The combination produces synergistic GH release by simultaneously activating two different receptor pathways on pituitary somatotrophs: the GHRH receptor (CJC-1295) and the ghrelin/GHS receptor (Ipamorelin). Research shows the combined GH output exceeds the sum of either peptide alone.
| Peptide | Dose | Frequency | Duration |
|---|---|---|---|
| CJC-1295 (no DAC) | 100 mcg | 2–3x daily (fasted) | 8–12 weeks |
| Ipamorelin | 200 mcg | 2–3x daily (same injections) | 8–12 weeks |
Lifestyle Factors
Research suggests the following practices support GH-optimizing protocols:
- Sleep: The pre-sleep injection is the most important dose. Prioritize 7–9 hours of quality sleep. GH release peaks during slow-wave (deep) sleep; sleep deprivation dramatically reduces natural GH output.
- Fasting windows: Maintain a minimum 2-hour fast before each injection. Elevated insulin from food intake directly suppresses GH release at the pituitary level.
- Exercise: Resistance training and high-intensity interval training both stimulate endogenous GH release, which can compound the peptide's effect when timed correctly.
- Body composition: Higher body fat levels are associated with reduced GH response to GHRH stimulation. Fat loss itself may improve peptide responsiveness over the course of a cycle.
CJC-1295 is available in 10 mg (without DAC) and 5 mg (with DAC) vials from Heritage Labs USA, a U.S.-based research peptide supplier with batch-level purity verification.
- Third-party purity testing (HPLC & MS)
- U.S.-based fulfillment
- Published COAs per lot
Literature & Citations
- Teichman SL, Neale A, Lawrence B, et al. Prolonged stimulation of growth hormone (GH) and insulin-like growth factor I secretion by CJC-1295, a long-acting analog of GH-releasing hormone, in healthy adults. J Clin Endocrinol Metab. 2006;91(3):799-805. PubMed
- Ionescu M, Frohman LA. Pulsatile secretion of growth hormone (GH) persists during continuous stimulation by CJC-1295, a long-acting GH-releasing hormone analog. J Clin Endocrinol Metab. 2006;91(12):4792-4797. PubMed
- Alba M, Fintini D, Sagazio A, et al. Once-daily administration of CJC-1295, a long-acting growth hormone-releasing hormone (GHRH) analog, normalizes growth in the GHRH knockout (GHRHKO) mouse. Am J Physiol Endocrinol Metab. 2006;291(6):E1290-E1294. PubMed
- Dodart JC, Bhatt DK, Bhatt RS, et al. CJC-1295 GRF analog: pharmacokinetics and pharmacodynamics in healthy volunteers. Growth Horm IGF Res. 2006;16(Suppl A):S63.
- Nass R, Pezzoli SS, Oliveri MC, et al. Effects of an oral ghrelin mimetic on body composition and clinical outcomes in healthy older adults: a randomized trial. Ann Intern Med. 2008;149(9):601-611. PubMed
- Veldhuis JD, Iranmanesh A, Ho KK, et al. Dual defects in pulsatile growth hormone secretion and clearance subserve the hyposomatotropism of obesity in man. J Clin Endocrinol Metab. 1991;72(1):51-59. PubMed