Peptide Reference · Growth Hormone
CJC-1295
CJC-1295 is a long-acting GHRH analogue that signals the pituitary to release growth hormone. It comes in two forms: with DAC (weekly) and without DAC, also called Mod GRF 1-29 (daily).
For research and educational purposes only · Not for human consumption
In Brief
CJC-1295 is a modified copy of the body’s growth-hormone-releasing hormone (GHRH). Like sermorelin, it tells the pituitary to make and release its own growth hormone, but it is engineered to last far longer in the body. It is most often paired with a GHRP such as ipamorelin, since the two act on different receptors for a larger combined pulse.
The key thing to understand is that CJC-1295 exists in two forms. With DAC it binds to blood albumin and lasts 6 to 8 days, so it is dosed weekly. Without DAC (sold as Mod GRF 1-29) it clears in about 30 minutes and is dosed daily to mimic natural pulses. It is not approved for human use and is banned in competitive sport.
Overview
CJC-1295 is a synthetic analogue of growth hormone releasing hormone (GHRH), based on the first 29 amino acids of GHRH (the GRF 1-29 fragment) with four amino-acid substitutions that make it resistant to enzymatic breakdown. Those substitutions are shared by both of its forms and are the reason it lasts far longer than sermorelin, the unmodified GRF 1-29.
What separates the two forms is a single add-on. CJC-1295 with DAC carries a Drug Affinity Complex, a chemical group that binds covalently to albumin in the blood, extending its half-life to roughly 6 to 8 days and raising growth hormone and IGF-1 for days after one injection. CJC-1295 without DAC, sold by compounding pharmacies as Mod GRF 1-29, lacks that group and clears in about 30 minutes, producing a short, natural-shaped pulse. Neither form is approved for human use; both are research compounds, commonly combined with a GHRP such as ipamorelin.
Common research uses
CJC-1295 has been studied or applied in the following contexts. None of these is an approved therapeutic indication.
- Growth hormone stimulation: raising endogenous growth hormone and IGF-1 through the GHRH receptor.
- Body composition and recovery: used informally, usually stacked with a GHRP, in the hope of supporting lean mass and recovery.
- Sustained IGF-1 elevation: the DAC form was studied specifically for its ability to keep IGF-1 elevated for several days after a single dose.
- Sleep: pre-bed dosing of the short-acting form aims to reinforce the natural overnight growth hormone pulse.
- Combination protocols: paired with ipamorelin or another GHRP, which acts on a separate receptor, for a larger combined pulse.
Informal use for recovery and body composition is unapproved, unregulated, and prohibited under WADA anti-doping rules.
Mechanism of action
CJC-1295 works through the GHRH pathway, the body’s own trigger for growth hormone:
- GHRH receptor agonism: binds the GHRH receptor on pituitary somatotroph cells, stimulating synthesis and release of growth hormone.
- Enzyme resistance: four amino-acid substitutions to the GRF 1-29 backbone block the enzymes that rapidly degrade natural GHRH and sermorelin.
- Albumin binding (DAC form): the DAC group latches onto albumin, a long-lived blood protein, so the peptide circulates for days rather than minutes.
- Preserved feedback: because growth hormone still passes through the body’s own regulation, the pulsatile pattern and safety brakes are partly retained, more so with the short-acting form.
- Complementary to GHRPs: acts on a different receptor than ghrelin-mimetic peptides, the basis for the common CJC-1295 plus ipamorelin stack.
Protocols
Quick Reference
The two forms are dosed very differently. Syringe units assume a 5 mg vial reconstituted with 2 mL BAC water (2.5 mg/mL) on a 1 mL / 100-unit insulin syringe.
The two forms
CJC-1295 is dosed according to which form you have. The long-acting DAC form is taken weekly; the short-acting form (Mod GRF 1-29) is taken daily. Add either schedule to your calendar below.
| Form | With DACLong-acting | Without DACMod GRF 1-29 |
|---|---|---|
| Recommended dose | 1–2 mg | 0.1–0.3 mg |
| Units (1 mL syringe) | 40–80 | 4–12 |
| Frequency | 1–2× per week | 1–3× daily |
| Timing | Any time of day | Before bed, fasted |
| Half-life | ~6–8 days | ~30 minutes |
| Duration | 8–12 wk on, 4 off | 8–12 wk on, 4 off |
| Add to calendar |
Community and practitioner dosing shown. Note: Dr. W. Seeds ↗ favours lower microgram clinical dosing (around 100 mcg), while Peptides For Men ↗ describes the milligram ranges above.
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Administration Routes
Both forms are given by subcutaneous injection. The form you have determines how often you dose and when.
Subcutaneous (SC)
Injection into the fat layer under the skin, usually the abdomen, with a short insulin needle. The standard route for both forms and easy to self-administer.
Timing & fasting
The short-acting form is taken on a relatively empty stomach, often before bed, since food blunts the growth hormone response. The DAC form maintains steady levels, so timing matters less.
Stacking
CJC-1295 is a GHRH, so it is commonly paired with a ghrelin-mimetic GHRP, which acts on a separate receptor, for a larger combined growth hormone pulse.
Reconstitution Guide
CJC-1295 is supplied as a lyophilised powder and must be reconstituted before use. New to this? See Peptides 101 for the fundamentals.
Gather supplies
Bacteriostatic water (BAC water), alcohol swabs, a 1 mL insulin syringe, and the peptide vial. BAC water contains 0.9% benzyl alcohol which prevents bacterial growth across multiple uses.
Calculate your dilution
A common dilution for a 5 mg vial: add 2 mL BAC water for a concentration of 2.5 mg/mL. At that strength a 2 mg DAC dose is about 80 units, and a 0.1 mg no-DAC dose about 4 units, on a U-100 syringe. Use the calculator below for your own numbers.
Add the water slowly
Wipe both vial tops with an alcohol swab. Draw the BAC water into the syringe. Insert the needle and angle it so the stream runs down the inside wall of the vial, not directly onto the powder cake.
Mix gently
Once all water is added, swirl gently in a circular motion until the powder is fully dissolved. Do not shake or vortex; agitation can degrade the peptide structure.
Store correctly
Reconstituted peptide: refrigerate at 2–8°C, away from light. Use within 4 weeks. Lyophilised powder: store frozen at −20°C for long-term. Label with the reconstitution date.
Reconstitution Calculator
Enter your vial size, water volume, and intended dose to calculate the exact volume and syringe markings.
⚠ This calculator is a reference tool only. Verify all calculations independently before use.
Active compound & chemistry
Both forms of CJC-1295 are built on a modified GRF 1-29 backbone: the first 29 amino acids of GHRH with four substitutions (at positions 2, 8, 15, and 27) that resist the enzymes which rapidly degrade natural GHRH. The short-acting form, Mod GRF 1-29, has a molecular weight of about 3,368 Da and a molecular formula of C₁₅₂H₂₅₂N₄₄O₄₂, with a half-life near 30 minutes.
CJC-1295 with DAC adds a Drug Affinity Complex: a lysine residue conjugated to maleimidopropionic acid, which forms a covalent bond with a cysteine on serum albumin. This raises the molecular weight to roughly 3,647 Da and, by tethering the peptide to long-lived albumin, extends its half-life to 6 to 8 days. Look up the compound in PubChem for full structural data, canonical SMILES, and InChI.
Evidence summary
CJC-1295 with DAC has some genuine human pharmacology data, while the broader recovery and body-composition claims rest on theory and the wider growth-hormone literature rather than dedicated trials.
Sustained GH and IGF-1 elevation in humans
In healthy adults, single injections of CJC-1295 with DAC produced dose-dependent increases in growth hormone and sustained elevations of IGF-1 lasting several days, confirming that albumin binding extends the peptide’s action well beyond that of unmodified GHRH.
Teichman SL et al. (2006) · J Clin Endocrinol Metab · View on PubMed →
Long-acting GHRH analogue design
CJC-1295 was developed as a proof of concept that attaching a drug-affinity complex to a GHRH fragment could create a long-acting analogue. The work established the albumin-binding strategy later used in other long-acting peptides.
Ionescu M, Frohman LA (2006) · J Clin Endocrinol Metab · View on PubMed →
Recovery and body-composition claims
Popular use for muscle, fat loss, and recovery extrapolates from the known effects of raising growth hormone and IGF-1. Dedicated controlled trials of CJC-1295 for these outcomes are lacking, so these benefits should be treated as unproven.
General GH literature · View on PubMed →
Warnings & cautions
- Not approved for human use in the United States, the European Union, the United Kingdom, Canada, or Australia. It is a research compound only.
- Banned in competitive sport by the World Anti-Doping Agency (WADA) under S2 (peptide hormones and releasing factors).
- Raises growth hormone and IGF-1, which is a theoretical concern for anyone with active or recent cancer, since these signals can promote cell growth.
- The DAC form persists for days. Its long half-life means both effects and any side effects cannot be quickly reversed once dosed.
- Common side effects include injection-site reactions, water retention or mild edema, facial flushing, headache, and transient tingling. Growth hormone can also reduce insulin sensitivity.
- Source quality is uncontrolled. Products sold for “research” are not regulated and may contain incorrect doses, the wrong form (DAC vs no-DAC), contaminants, or different compounds than labelled.
References
- Teichman SL, Neale A, Lawrence B, et al. (2006). Prolonged stimulation of growth hormone and insulin-like growth factor I secretion by CJC-1295, a long-acting analog of GHRH, in healthy adults. Journal of Clinical Endocrinology & Metabolism. PubMed
- Ionescu M, Frohman LA. (2006). Pulsatile secretion of growth hormone (GH) persists during continuous stimulation by CJC-1295, a long-acting GH-releasing hormone analog. Journal of Clinical Endocrinology & Metabolism. PubMed
- Seeds WA. (2020). Peptide Protocols: Volume One. Reference text
Reference links resolve to PubMed search queries or source pages. Verify the specific record before citing.
Important: This page is educational and reference-only. CJC-1295 is not approved for human use and is prohibited in competitive sport. Nothing here is medical advice. Any research must comply with applicable laws and institutional review requirements. Consult a qualified healthcare professional before making decisions about your health.