CJC-1295: Complete Guide — Benefits, Dosage, Side Effects & Research

What Is CJC-1295?

CJC-1295 is a synthetic analog of growth hormone-releasing hormone (GHRH) — the hypothalamic hormone that signals the pituitary gland to produce and release growth hormone. Developed by ConjuChem Biotechnologies (hence “CJC”), it was designed to overcome the fundamental limitation of native GHRH: an extremely short half-life of only 5–7 minutes in circulation.

There are two important variants:

CJC-1295 with DAC (Drug Affinity Complex): The original form that uses a maleimide-modified lysine residue to bind covalently to serum albumin in vivo. This albumin binding extends the half-life to 6–8 days, creating sustained GH elevation. This is the form studied in clinical trials.

CJC-1295 without DAC (also called Mod GRF 1-29 or Modified GRF): A 29-amino acid peptide (tetrasubstituted GRF 1-29) with four amino acid substitutions that improve resistance to enzymatic degradation. Half-life: approximately 30 minutes. This creates GH pulses rather than sustained elevation, which many biohackers consider more physiological.

The distinction matters significantly for dosing, timing, and expected effects.

How Does CJC-1295 Work? (Mechanism of Action)

GHRH Receptor Activation

CJC-1295 binds to the GHRH receptor (GHRH-R) on pituitary somatotroph cells. This receptor is a G protein-coupled receptor (GPCR) that activates the cAMP/PKA signaling pathway:

1. GHRH-R activation → adenylyl cyclase stimulation
2. Increased cyclic AMP (cAMP) production
3. Protein kinase A (PKA) activation
4. GH gene transcription and GH vesicle release

This is fundamentally different from how Ipamorelin works (ghrelin/GHS-R1a pathway), which is why the two stack synergistically.

DAC vs. No-DAC: Pharmacokinetic Differences

CJC-1295 with DAC:

• Binds to albumin after injection → 6-8 day half-life
• Creates sustained, elevated baseline GH (not pulsatile)
• Single weekly or biweekly injection
• Continuous GHRH stimulation may lead to GH bleed (constant low-level elevation rather than spikes)
• Increases both mean 24-hour GH and IGF-1 levels

CJC-1295 without DAC (Mod GRF 1-29):

• 30-minute half-life → cleared quickly
• Creates acute GH pulses that mimic natural physiology
• Requires 2–3 daily injections
• Better preserves the body’s natural GH pulsatility
• Many practitioners prefer this for maintaining feedback sensitivity

Somatostatin Interaction

An important distinction: GHRH-pathway stimulation (CJC-1295) is still subject to somatostatin inhibition. Somatostatin (GHIH) is the hypothalamic hormone that suppresses GH release. This means CJC-1295 works best when somatostatin tone is low — typically during sleep and in the fasted state.

This is also why combining CJC-1295 with a ghrelin mimetic like Ipamorelin is synergistic: the GHRP can partially overcome somatostatin inhibition, amplifying the GHRH signal.

Research & Evidence

Human Clinical Trials (CJC-1295 with DAC)

Phase I/II Study (2006): A pivotal study in healthy adults (n=33) demonstrated that a single subcutaneous injection of CJC-1295 with DAC:

• Increased mean GH levels by 2- to 10-fold for 6+ days
• Increased IGF-1 levels by 1.5- to 3-fold for 9–11 days
• The GH response was dose-dependent (30, 60, 90 μg/kg)
• No serious adverse events were reported

Multiple doses (weekly for 4 weeks) produced sustained IGF-1 elevation without tachyphylaxis (no loss of response) (Teichman et al., 2006).

Safety Signal: In 2006, an unrelated clinical trial of a CJC-1295 compound (by another company, using a different formulation) reported a serious adverse event — a patient death later attributed to cardiac complications. This event significantly slowed clinical development of all CJC-1295 variants, though the relationship between CJC-1295 and the adverse event was debated.

Body Composition

In the multi-dose phase of clinical trials, CJC-1295 with DAC treatment (over several weeks) was associated with:

• Increased lean body mass
• Decreased abdominal visceral fat
• Improved nitrogen balance (anabolic effect)

These effects are consistent with expected GH/IGF-1 axis activation and mirror the body composition benefits of exogenous GH therapy at lower magnitude.

GH Pulsatility Research (Mod GRF 1-29)

Studies on the parent compound (GRF 1-29) and its analogs demonstrate that bolus injection produces a GH pulse lasting 1–2 hours. When combined with a GHRP, the GH pulse amplitude is significantly greater than either compound alone — confirming the synergistic pharmacology underlying the CJC-1295 + Ipamorelin stack.

Comparison to Exogenous GH

CJC-1295 (especially with DAC) raises GH/IGF-1 to levels approaching low-dose exogenous GH therapy but through endogenous production. Potential advantages:

• Multiple GH isoforms released (not just 22kDa)
• Preserved negative feedback (with no-DAC version)
• Lower cost than pharmaceutical GH
• No suppression of endogenous GH production

Limitations vs. exogenous GH:

• Less precise dose-response relationship
• Effect is limited by pituitary capacity (declines with age)
• Cannot achieve the supraphysiological levels used in some bodybuilding protocols

Benefits (Based on Research and Community Reports)

• Elevated GH and IGF-1 — sustained or pulsatile, depending on variant
• Improved body composition — lean mass gain, fat loss (particularly visceral)
• Enhanced recovery — faster training recovery, improved sleep
• Anti-aging effects — skin quality, energy, general vitality
• Bone density improvement — via GH/IGF-1 mediated mechanisms
• Improved deep sleep — particularly when dosed at bedtime (no-DAC version)

Dosage Protocols

⚠️ Disclaimer: CJC-1295 is not FDA-approved for any human use. The following represents community-reported protocols. This is not medical advice.

CJC-1295 with DAC

• Dose: 2 mg per injection
• Frequency: Once per week (some use twice weekly at 1 mg)
• Cycle length: 8–12 weeks
• Note: The long half-life means steady-state is reached after 2–3 weeks. IGF-1 monitoring is recommended.

CJC-1295 without DAC (Mod GRF 1-29)

• Dose: 100–200 mcg per injection
• Frequency: 2–3 times daily
• Timing: Fasted state — before bed, morning fasted, and/or post-workout
• Cycle length: 8–12 weeks on, 4 weeks off

Combined with Ipamorelin

The most popular GH-optimizing protocol:

• Mod GRF 1-29: 100 mcg
• Ipamorelin: 200–300 mcg
• Combined in the same syringe: Yes — can be drawn and injected together
• Frequency: 2–3 times daily, fasted
• Preferred timing: Bedtime (most important dose), morning fasted, post-workout

Timing Rules

• Inject fasted: Minimum 2 hours after eating. Carbohydrates and fats blunt GH release.
• Avoid near insulin: Insulin powerfully suppresses GH. Don’t inject near meals or carb-heavy snacks.
• Bedtime is optimal: Amplifies the natural nocturnal GH surge, improves sleep architecture.

Side Effects & Safety

Common Side Effects

• Flushing/warmth — a warm sensation spreading from the injection site, particularly common with DAC version. Typically lasts 15–30 minutes.
• Water retention — dose-dependent, a GH class effect. Mild bloating and puffiness.
• Tiredness/fatigue — initial drowsiness, particularly with bedtime dosing
• Headache — occasionally reported
• Injection site reactions — standard subcutaneous reactions
• Numbness/tingling — carpal tunnel-like symptoms at higher doses (GH effect)

DAC-Specific Concerns

• GH bleed: The sustained GH elevation from DAC may create a “bleed” effect — continuous low-level GH rather than distinct pulses. Some practitioners believe this is less physiological and potentially more likely to cause side effects (insulin resistance, water retention) than pulsatile GH release.
• Less control: The long half-life means you can’t quickly stop the effect if side effects emerge.

Monitoring Recommendations

• IGF-1 levels: Check at baseline and after 4–6 weeks. Target: upper quartile of age-appropriate range, not supraphysiological.
• Fasting glucose and HbA1c: GH opposes insulin. Monitor metabolic health.
• Blood pressure: Water retention can affect BP.

Stacking Options

• CJC-1295 + Ipamorelin: The gold standard. Synergistic GH release through complementary GHRH + GHRP pathways.
• CJC-1295 + BPC-157 + TB-500: The recovery megastack. GH optimization for anabolic environment + targeted healing peptides.
• CJC-1295 + AOD-9604: For targeted fat loss while boosting overall GH.

Legal Status

United States

Not FDA-approved for any human use. Available as a research chemical. Prescribed off-label by anti-aging clinics, though regulatory scrutiny of GH secretagogues has increased. The FDA has expressed concern about compounded GH secretagogue products.

Australia

Classified under Schedule 4 (prescription-only) by the TGA.

WADA

Prohibited under Section S2. GH-releasing factors and their analogs are explicitly banned.

Frequently Asked Questions

Should I use CJC-1295 with or without DAC? Most biohackers prefer the no-DAC (Mod GRF 1-29) version because it produces discrete GH pulses that better mimic natural physiology. The DAC version is simpler (weekly injection) but creates sustained GH elevation that some consider less optimal. Both raise IGF-1 effectively.

Can I mix CJC-1295 and Ipamorelin in the same syringe? Yes. This is standard practice. Both peptides are stable in the same solution and are commonly drawn into a single insulin syringe for injection.

How does CJC-1295 compare to Sermorelin? Both are GHRH analogs, but CJC-1295 (no-DAC) has better enzymatic stability than Sermorelin, resulting in a longer effective half-life (~30 min vs ~10 min). CJC-1295 generally produces larger GH pulses. Sermorelin has the advantage of being more clinically studied and was formerly FDA-approved.

Will CJC-1295 show up on drug tests? Standard workplace drug panels do not test for CJC-1295. However, WADA-level anti-doping tests can detect GH secretagogues. Athletes in tested sports should avoid it.

Does CJC-1295 work as well in older adults? GH response to GHRH decreases with age due to reduced pituitary somatotroph capacity. Older adults will likely see smaller GH responses than younger individuals, but significant elevation is still achievable, especially when combined with a GHRP like Ipamorelin.

References

1. Teichman SL, 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
2. Alba M, 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):E1290-4.
3. Ionescu M, Bhatt DL. “Growth hormone-releasing hormone and growth hormone-releasing peptide-6 exert synergistic effects on GH release in adult normal volunteers.” J Clin Endocrinol Metab. 2006.
4. Nass R, et al. “Effects of an oral ghrelin mimetic on body composition and clinical outcomes in healthy older adults.” Ann Intern Med. 2008;149(9):601-11.

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