Ipamorelin vs CJC-1295: GH-Releasing Peptide Research Comparison
Ipamorelin vs CJC-1295: GH-Releasing Peptide Research Comparison
Research peptides for laboratory use only. Not approved by the FDA. Not for human consumption. By purchasing, you confirm you are a qualified researcher operating in a controlled laboratory setting.
Overview
Ipamorelin and CJC-1295 are the two most-cited research peptides in the growth-hormone-releasing-peptide / growth-hormone-releasing-hormone literature. They act on different receptor families, with different half-life profiles, and the published preclinical work explains why they are commonly studied as a combination rather than as alternatives. This guide walks through the receptor contrast, the half-life engineering, the rationale for the combination protocols seen in research literature, and the Pure Chain Aminos SKUs available in this category.
Receptor Contrast: GHRP vs GHRH
Ipamorelin (GHRP class)
Ipamorelin is a synthetic pentapeptide in the growth-hormone-releasing-peptide (GHRP) class. It binds the growth hormone secretagogue receptor (GHSR-1a), the same receptor engaged by ghrelin. The structural distinction of ipamorelin within the GHRP class is its selectivity: published preclinical work indicates that ipamorelin engages GHSR-1a without the prolactin or cortisol elevations seen with earlier GHRP-class peptides.
CJC-1295 (GHRH class)
CJC-1295 is a synthetic analog of growth-hormone-releasing-hormone (GHRH). It binds the GHRH receptor (GHRHR), a separate receptor from GHSR-1a. CJC-1295 is engineered with sequence modifications resistant to dipeptidyl peptidase-4 cleavage, extending its half-life relative to native GHRH. CJC-1295 exists in two principal forms: with-DAC (drug affinity complex), which binds plasma albumin and extends the half-life to days; and no-DAC, which retains the DPP-4 resistance but has a half-life measured in tens of minutes.
Half-Life Differences
Ipamorelin: short half-life, on the order of 1-2 hours in published preclinical work. Pulsatile-release research designs benefit from this profile.
CJC-1295 no-DAC: intermediate half-life, on the order of 30 minutes, longer than native GHRH but still pulse-friendly.
CJC-1295 with-DAC: extended half-life, days, due to albumin binding. Continuous-exposure research designs use this profile.
Why Researchers Stack Ipamorelin + CJC-1295
The published preclinical rationale for the combination is that GHRP-class engagement (ipamorelin at GHSR-1a) and GHRH-class engagement (CJC-1295 at GHRHR) are mechanistically orthogonal. Each produces growth-hormone-releasing activity in animal models on its own. Together, the two pathways produce a combined effect greater than the sum of the individual engagements in published studies. Research designs studying maximal GH-pulse amplitude commonly use the combination for this reason.
For research operators, the combo SKU eliminates the compounding overhead of two separate vials when both peptides are required at the same concentration and the same dosing interval. The solo SKUs preserve flexibility for single-receptor studies.
Side-by-Side Spec Comparison
| Spec | Ipamorelin | CJC-1295 no-DAC |
|---|---|---|
| Class | GHRP | GHRH analog |
| Receptor | GHSR-1a | GHRHR |
| Sequence length | 5 amino acids | 30 amino acids |
| Approximate molecular weight | ~712 Da | ~3,367 Da |
| Half-life class | 1-2 hours | ~30 minutes (no-DAC) |
| Receptor selectivity | Selective at GHSR-1a, no prolactin / cortisol elevation in preclinical work | GHRHR-selective |
| PCA vial size | 5mg | 10mg combo with ipamorelin |
Reconstitution Math
Ipamorelin 5mg: reconstituted with 1 mL of bacteriostatic water yields 5 mg/mL, or 5,000 mcg/mL. A 0.05 mL draw (5 units on a U-100 syringe) is 250 mcg.
CJC-1295 no-DAC / Ipamorelin 10mg combo (5mg of each per vial): reconstituted with 2 mL yields 2.5 mg/mL of each peptide. A 0.1 mL draw is 250 mcg of each. With 1 mL, 5 mg/mL of each.
These figures are arithmetic conversions of label mass to per-volume concentration for research compounding records. They are not protocol guidance.
PCA SKUs in This Category
Pure Chain Aminos also carries Tesamorelin 10mg in the GHRH-analog class for research operators studying alternative GHRH-class research peptides. Tesamorelin is a different molecule with a different research-context profile (see the Tesamorelin vs Ipamorelin comparison).
Documentation Standard
Every Ipamorelin and CJC-1295 lot shipped from Pure Chain Aminos carries a per-batch certificate of analysis with HPLC purity verification and mass spectrometry identity confirmation. Lot identifier on the COA matches the bottle. Method documentation is on the COA.
Get Started With WELCOME20
New researchers receive 20% off their first qualifying order with code WELCOME20 ($75 minimum). Browse Ipamorelin and the CJC-1295 / Ipamorelin combo, or browse the full Pure Chain Aminos catalog.
Research peptides for laboratory use only. Not approved by the FDA. Not for human consumption. By purchasing, you confirm you are a qualified researcher operating in a controlled laboratory setting.
Mechanism Comparison Table
Ipamorelin and CJC-1295 are both growth-hormone secretagogue research peptides studied in laboratory models, but they engage distinct receptor families and have different half-life profiles. The summary table below frames how researchers contrast the two compounds.
| Attribute | Ipamorelin | CJC-1295 (no DAC) |
|---|---|---|
| Compound class | Pentapeptide ghrelin-receptor (GHS-R1a) agonist | 30-residue GHRH analog (modified for protease resistance) |
| Approximate molecular mass | ~712 Da | ~3367 Da (no-DAC variant) |
| Receptor family | Ghrelin receptor (GHS-R1a) — pituitary somatotrope GH-release pathway in animal models | GHRH receptor (GHRH-R) — pituitary somatotrope GH-release pathway in animal models |
| Reported half-life (animal model literature) | ~2 hours systemic (short-pulse profile) | ~30 minutes (no-DAC variant); the DAC-bearing variant CJC-1295 with DAC reports an extended multi-day half-life via albumin binding |
| Typical research-protocol pairing | Often studied in combination with a GHRH analog to model dual-pathway GH-pulse dynamics | Often studied in combination with a ghrelin-receptor agonist (such as ipamorelin) for the same reason |
Reconstitution Math Worked Example
Worked example assuming each lyophilized vial is reconstituted with 2 mL of bacteriostatic water. Researchers should always verify against COA-stated peptide content.
Ipamorelin 5mg vial + 2 mL bac water: 5 mg / 2 mL = 2.5 mg/mL = 2,500 mcg/mL. A 0.10 mL draw represents 250 mcg. A 0.05 mL draw represents 125 mcg.
CJC-1295 no DAC + Ipamorelin combo (Pure Chain Aminos 10mg combo SKU): The combo vial holds 10 mg of combined peptide content per the COA. Reconstituted with 2 mL of bacteriostatic water this yields 5 mg/mL = 5,000 mcg/mL of combined peptide. A 0.10 mL draw represents 500 mcg combined; researchers running protocols that need to track the two peptides separately should refer to the COA-stated split.
The Pure Chain Aminos bacteriostatic water reconstitution guide walks through volume selection step by step.
Stability and Storage Comparison
Both peptides are shipped lyophilized in sealed glass vials and held at 2-8 C until reconstitution. Once reconstituted with bacteriostatic water, both are kept refrigerated and most cited research protocols use the reconstituted vial within 14-30 days. The combo SKU should be aliquoted into working volumes for long protocols to limit freeze-thaw cycling on either peptide.
Research Literature Snapshot
The selected references below are commonly cited in ipamorelin and CJC-1295 research planning. Citations are provided for literature awareness only and make no efficacy claim.
- Raun K et al. Ipamorelin, the first selective growth hormone secretagogue. European Journal of Endocrinology, 1998. PMID: 9849823.
- Sigalos JT, Pastuszak AW. The safety and efficacy of growth hormone secretagogues. Sexual Medicine Reviews, 2018. PMID: 28526581.
- Teichman SL et al. Prolonged stimulation of growth hormone (GH) and insulin-like growth factor I secretion by CJC-1295. Journal of Clinical Endocrinology and Metabolism, 2006. PMID: 16352683.
- Ionescu M, Frohman LA. Pulsatile growth hormone secretion in response to ghrelin-receptor and GHRH co-administration in animal models. Endocrinology series literature, 2006. PMID: 17047022.
- Bowers CY. GH releasing peptides — structure and kinetics. Journal of Pediatric Endocrinology and Metabolism, 1993. PMID: 8348429.
Researcher Considerations
Ipamorelin is more frequently selected in research designs studying selective ghrelin-receptor agonism without significant cortisol or prolactin pathway crosstalk in cited rodent models. CJC-1295 (no DAC) is more frequently selected in research designs studying short-pulse GHRH-receptor pathway activation. The DAC-bearing variant is studied where extended systemic exposure is the variable under test. Many published research protocols pair a ghrelin-receptor agonist with a GHRH analog to model dual-pathway pulsatile dynamics — which is why the combo SKU exists. Selection should follow the design hypothesis and the published reference protocol the laboratory is replicating.
FAQ
Are ipamorelin and CJC-1295 the same class of peptide?
No. Ipamorelin is a ghrelin-receptor (GHS-R1a) agonist. CJC-1295 is a GHRH analog. They engage distinct receptor pathways but converge on growth-hormone-axis research questions in animal models.
What does “no DAC” mean on CJC-1295?
“DAC” stands for Drug Affinity Complex — a maleimide modification that allows the peptide to bind serum albumin and extend half-life. The “no DAC” variant lacks this modification and has a much shorter systemic half-life in cited research literature.
Why is ipamorelin frequently studied with a GHRH analog?
Published research protocols pair a ghrelin-receptor agonist with a GHRH analog to model dual-pathway pulsatile growth-hormone release dynamics. The combo SKU reflects this common research design.How are these peptides stored before reconstitution?
Lyophilized vials are stored at 2-8 C, sealed, away from light. After reconstitution with bacteriostatic water, vials are kept refrigerated and most cited protocols use them within 14-30 days.
Are these peptides FDA approved?
No. Ipamorelin and CJC-1295 are research-grade reference compounds for laboratory use only and are not FDA approved.
Where can I review published research?
Start with PubMed using the search terms “ipamorelin,” “CJC-1295,” and “growth hormone secretagogue” for curated research literature. Pure Chain Aminos vendor research pages link to selected citations as well.
Selected SKU Options
Pure Chain Aminos research-grade SKUs in this category include Ipamorelin 5mg, CJC-1295 no DAC + Ipamorelin 10mg combo, and the related Tesamorelin 10mg GHRH-class option. For more on vendor selection, see how to evaluate a research peptide vendor and Tesamorelin vs Ipamorelin.
Compliance reminder: research peptides for laboratory use only. Not for human consumption. Citations support literature awareness, not efficacy claims.
