Skip to content
Specimen Atlas of Research Peptides81 plates · MIT
Side-by-side · Research reference

CJC-1295 (no DAC)vsTriptorelin

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
BFDA-ApprovedHUMAN-REVIEWED16/64 cited
CJC-1295 (no DAC)
Short-acting GHRH · No DAC variant
100 mcgPer doseTeichman 2006
~30 minHalf-lifeIonescu 2006
Phase 1Evidence levelTeichman 2006Sigalos 2018
SQ · Pre-sleep · 1–2×/day
Triptorelin
GnRH Agonist · FDA-Approved
3.75–22.5 mgDepot dose rangeYee 2025Chen 2024
<50 ng/dLTestosterone target
1–6 monthsDepot durationYee 2025Chen 2024
IM · Depot Injection · Monthly to 6-MonthlyYee 2025

01Mechanism of Action

Parameter
CJC-1295 (no DAC)
Triptorelin
Primary target
Pituitary GHRH receptorTeichman 2006
Pituitary GnRH receptorsUnknown 2012
Pathway
GHRH-R → Gαs → cAMP → PKA → GH vesicle exocytosisTeichman 2006
GnRH receptor agonism → initial flare (LH/FSH spike) → receptor desensitization → sustained LH/FSH suppression
Downstream effect
Pulsatile GH release matching physiological pattern; subsequent IGF-1 elevationIonescu 2006
Castration-level suppression of testosterone (men) and estrogen (women) within 2–4 weeks post-flare
Feedback intact?
Yes — short pulse preserves somatostatin negative feedbackIonescu 2006
No — bypasses physiological pulsatility; continuous agonism produces paradoxical suppression
Origin
Modified human GRF 1-29 with four substitutions (D-Ala²/Gln⁸/Ala¹⁵/Leu²⁷) for protease resistanceTeichman 2006
Synthetic decapeptide analogue of native GnRH with amino acid substitutions for enhanced receptor affinity and stability
Antibody development
Not reported in short-term studies

02Dosage Protocols

Parameter
CJC-1295 (no DAC)
Triptorelin
Standard dose
100 mcg per injectionTeichman 2006
Often paired with ipamorelin in same syringe.
Frequency
1–2× daily (pre-sleep ± morning)
Every 1, 3, or 6 months per formulation
Lower / starter dose
50 mcg per dose
Evidence basis
Phase 1 (CJC-1295 with DAC); analog dataTeichman 2006Ionescu 2006
No-DAC variant is less studied directly; PK extrapolated from native GHRH.
Multiple Phase 3 RCTs · FDA-approved 1999
Duration
8–12 weeks on / 4 off (anecdotal)
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.
1-month depot
3.75 mg IM
Most common formulation for prostate cancer.
3-month depot
11.25 mg IMYee 2025
Reduced injection frequency.
6-month depot
22.5 mg IMYee 2025Chen 2024
Long-acting formulation; improved adherence in real-world use.Yee 2025
Administration route
Intramuscular (IM) — gluteal or deltoid
Indication: Prostate cancer
Advanced (metastatic or locally advanced)
Androgen deprivation therapy (ADT) backbone.
Indication: Endometriosis
3.75 mg monthly
FDA-approved; typically 6-month course.
Indication: Central precocious puberty
Pediatric use (≥2 years)Jia 2025
Weight-based dosing per FDA label.
Duration (prostate cancer)
Continuous or intermittent ADT protocolsPreston 2024
Intermittent ADT may reduce side effects; cardiovascular risk similar to continuous.
Monitoring
Serum testosterone, PSA (prostate cancer), bone density, lipids, glucose

04Side Effects & Safety

Parameter
CJC-1295 (no DAC)
Triptorelin
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
Initial flare symptoms
Bone pain, urinary obstruction, spinal cord compression (first 2 weeks)
Antiandrogen co-treatment (bicalutamide) mitigates flare in metastatic disease.
Cardiovascular events
MI, stroke, arrhythmia — GnRH agonists show higher CV risk vs antagonists in meta-analysesPatel 2025Preston 2024
Hot flashes
Very common (>60%); vasomotor instability
Bone loss / Osteoporosis
Accelerated bone mineral density decline; fracture risk ↑Friedrich 2025
Baseline DEXA scan recommended; bisphosphonates or denosumab may be indicated.
Metabolic syndrome
Weight gain, insulin resistance, dyslipidemia, diabetes risk
Sexual dysfunction
Erectile dysfunction, loss of libido (expected pharmacological effect)Jia 2025
Injection site reactions
Pain, erythema, sterile abscess (rare with depot formulations)
Gynecomastia / Breast tenderness
Common (10–20%); peripheral aromatization of residual androgens
Fatigue / Mood changes
Anemia, depression, cognitive changes reported in long-term ADT
Hepatotoxicity
Transient transaminase elevations; clinically apparent liver injury rare
Racial differences (ADT)
Black veterans show higher CV event rates vs White veterans on GnRH agonists
Absolute Contraindications
CJC-1295 (no DAC)
  • ·Active malignancy or cancer history
  • ·Pregnancy / breastfeeding
  • ·Disrupted hypothalamic-pituitary axis
Triptorelin
  • ·Hypersensitivity to triptorelin, GnRH, or GnRH agonist analogues
  • ·Pregnancy (Category X)
Relative Contraindications
CJC-1295 (no DAC)
  • ·Untreated diabetes
  • ·Severe insulin resistance
Triptorelin
  • ·Active cardiovascular disease — consider GnRH antagonist alternative
  • ·Metastatic vertebral disease with spinal cord compression risk (flare hazard)
  • ·Severe urinary obstruction — may worsen during flare
  • ·Osteoporosis or high fracture risk (requires bone-protective therapy)

05Administration Protocol

Parameter
CJC-1295 (no DAC)
Triptorelin
1. Reconstitution
Add 2 mL bacteriostatic water to 2 mg vial → 1 mg/mL = 100 mcg per 0.1 mL. Roll gently.
Choose 1-month (3.75 mg), 3-month (11.25 mg), or 6-month (22.5 mg) depot based on adherence needs and clinical context. 6-month formulation shows improved real-world adherence in Asia-Pacific cohorts.
2. Injection site
Subcutaneous, abdomen or thigh. Rotate sites.
Intramuscular — gluteal or deltoid muscle. Use 21–23G needle. Aspirate to confirm non-vascular placement. Rotate sites with repeat injections.
3. Timing
Pre-sleep preferred. Often combined with ipamorelin in the same syringe.
For metastatic prostate cancer: co-administer antiandrogen (e.g., bicalutamide 50 mg daily) starting 1 week before first injection and continuing 2–4 weeks to prevent tumor flare.
4. Storage
Lyophilised: room temp, protected from light. Reconstituted: refrigerate 2–8 °C, use within 30 days.
Baseline: testosterone, PSA, bone density (DEXA), lipids, glucose. Follow-up: testosterone at 4 weeks (confirm <50 ng/dL castration), PSA monthly × 3, then quarterly. Annual DEXA for bone loss.
5. Needle
29–31G, 4–8 mm insulin syringe.
Store vials at room temperature (20–25 °C), protect from light. Do not freeze. Reconstituted suspension should be used immediately.
6. Intermittent ADT protocol (optional)
Some protocols use on-treatment periods (9–12 months) alternating with off-treatment intervals until PSA rises. Cardiovascular risk appears similar to continuous ADT.

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
Triptorelin
— no documented stacks