Side-by-side · Research reference

CJC-1295 (no DAC)vsP21

Side-by-side comparison across mechanism, dosage, evidence, side effects, administration, and stack synergies. Citations on every claim where available.

APhase 1HUMAN-REVIEWED15/51 cited

BAnimal-MechanisticHUMAN-REVIEWED8/36 cited

CJC-1295 (no DAC)

Short-acting GHRH · No DAC variant

100 mcgPer doseTeichman 2006

~30 minHalf-lifeIonescu 2006

Phase 1Evidence levelTeichman 2006 Sigalos 2018

SQ · Pre-sleep · 1–2×/day

P21

CNTF-Derived Neuropeptide · Animal Model Evidence

CNTFR/gp130Primary receptorGuo 2022

Animal onlyEvidence level

NeurogenesisPrimary effectJia 2020 Mottolese 2024

SQ · Site unspecified · Frequency unknown

01Mechanism of Action

Parameter

CJC-1295 (no DAC)

P21

Primary target

Pituitary GHRH receptorTeichman 2006

CNTF receptor alpha (CNTFRα) / LIF receptor (LIFR) / gp130 complex on neural stem cells

Pathway

GHRH-R → Gαs → cAMP → PKA → GH vesicle exocytosisTeichman 2006

CNTF mimetic → CNTFRα/LIFR/gp130 heterotrimer → JAK/STAT3 signaling → neurogenesis, stem cell proliferation, neuroprotection

Downstream effect

Pulsatile GH release matching physiological pattern; subsequent IGF-1 elevationIonescu 2006

Increased neural stem cell self-renewal, globose basal cell activation (Mash1+ cells), olfactory sensory neuron regeneration, hippocampal neurogenesis, neuroprotection in developmental disorders

Feedback intact?

Yes — short pulse preserves somatostatin negative feedbackIonescu 2006

—

Origin

Modified human GRF 1-29 with four substitutions (D-Ala²/Gln⁸/Ala¹⁵/Leu²⁷) for protease resistanceTeichman 2006

Small-molecule peptide mimetic derived from full-length ciliary neurotrophic factor (CNTF), designed to retain receptor activation with improved pharmacokineticsMottolese 2024

Antibody development

Not reported in short-term studies

—

02Dosage Protocols

Parameter

CJC-1295 (no DAC)

P21

Standard dose

100 mcg per injectionTeichman 2006

Often paired with ipamorelin in same syringe.

—

Frequency

1–2× daily (pre-sleep ± morning)

—

Lower / starter dose

50 mcg per dose

—

Evidence basis

Phase 1 (CJC-1295 with DAC); analog dataTeichman 2006 Ionescu 2006

No-DAC variant is less studied directly; PK extrapolated from native GHRH.

Animal models only

CDKL5 KO mice, methimazole-induced olfactory injury, CNTF-/- knockout models.Mottolese 2024 Cox 2026 Jia 2020

Duration

8–12 weeks on / 4 off (anecdotal)

Not specified

Reconstitution

Bacteriostatic water

—

Timing

Pre-sleep + fasted preferred

—

Half-life

~30 minIonescu 2006

Short pulse vs CJC-1295-DAC (~8 days). Choose no-DAC for pulsatile, DAC for sustained.

—

Human dosing

—

No established protocol

No clinical trial data available.

Animal models (mice)

—

Dose and route not specified in abstractsMottolese 2024 Jia 2020

In vitro and in vivo studies demonstrate efficacy; precise dosing protocols not disclosed.

Route

—

Presumed subcutaneous or intraperitoneal (animal studies)

04Side Effects & Safety

Parameter

CJC-1295 (no DAC)

P21

Injection site reaction

Erythema, mild pruritus

—

Flushing / headache

Common transient effect

—

Cortisol elevation

Minimal at standard doses

—

Prolactin elevation

Minimal

—

Glucose intolerance

Possible at high cumulative doses

—

IGF-1 elevation

Dose-dependent; monitor with chronic use

—

Cancer risk

Contraindicated in active malignancy (GH/IGF-1 axis)

—

Pregnancy / OB

Avoid

—

Human safety data

—

None available

No clinical trials in humans.

Animal tolerability

—

Well-tolerated in mouse models; no toxicity reported in available abstracts

Theoretical risks

—

Uncontrolled stem cell proliferation, immune response to peptide, unknown long-term CNS effects

Absolute Contraindications

CJC-1295 (no DAC)

·Active malignancy or cancer history
·Pregnancy / breastfeeding
·Disrupted hypothalamic-pituitary axis

P21

·Use in humans not validated

Relative Contraindications

CJC-1295 (no DAC)

·Untreated diabetes
·Severe insulin resistance

P21

·Active malignancy (theoretical — neurotrophic signaling may affect tumour growth)
·Pregnancy or lactation (no safety data)

05Administration Protocol

Parameter

CJC-1295 (no DAC)

P21

1. Reconstitution

Add 2 mL bacteriostatic water to 2 mg vial → 1 mg/mL = 100 mcg per 0.1 mL. Roll gently.

Not established. No FDA approval, no clinical trial data.

2. Injection site

Subcutaneous, abdomen or thigh. Rotate sites.

In vivo studies used systemic administration (route not specified in abstracts) in mouse models of neurodegeneration, olfactory injury, and CDKL5 deficiency disorder. In vitro studies used primary cell cultures.

3. Timing

Pre-sleep preferred. Often combined with ipamorelin in the same syringe.

—

4. Storage

Lyophilised: room temp, protected from light. Reconstituted: refrigerate 2–8 °C, use within 30 days.

—

5. Needle

29–31G, 4–8 mm insulin syringe.

—

06Stack Synergy

CJC-1295 (no DAC)

+ Ipamorelin

Strong

View Ipamorelin →

CJC-1295 (no DAC) and ipamorelin are the canonical "GHRH + GHRP" dual-axis stack at physiological timing. Both peak within 30 min and clear within 2 hours, producing a sharp, high-amplitude GH pulse closely resembling natural physiology. Preferred over the CJC-1295-DAC + ipamorelin stack when pulsatility (vs sustained elevation) is the goal.

CJC-1295 (no DAC): 100 mcg SQ · pre-sleep
Ipamorelin: 200–300 mcg SQ · same injection
Primary benefit: Pulsatile GH stimulation, recovery, body composition

Teichman 2006 Raun 1998

P21

— no documented stacks