CJC-1295 / Ipamorelin

Overview

CJC-1295 and ipamorelin are usually administered together as a paired growth-hormone secretagogue stack. The two peptides target different receptors that converge on the same outcome: stimulating the pituitary gland to release more endogenous growth hormone, in pulses that approximate natural physiology. This is a fundamentally different approach from injecting exogenous human growth hormone (HGH) — and the regulatory and safety profiles differ accordingly.

CJC-1295 exists in two forms. The version with DAC (Drug Affinity Complex) attaches to plasma albumin and has a 6–8 day half-life, making once-weekly or twice-weekly dosing possible. The version without DAC has a half-life of about 30 minutes, requiring multiple daily doses but producing tighter pulsatile spikes more closely matching natural GH rhythm. Most clinical and bodybuilding-forum protocols favor the no-DAC form precisely because of the pulsatility argument.

Ipamorelin is a selective ghrelin receptor agonist — meaning it triggers GH release through a separate pathway than CJC-1295 (which is a GHRH analog). Crucially, ipamorelin does not raise cortisol or prolactin at therapeutic doses, distinguishing it from older secretagogues like GHRP-6. Combined with CJC-1295, the two produce synergistic pulsatile GH release.

How they work

CJC-1295 is a 30-amino-acid analog of growth hormone-releasing hormone (GHRH), the natural hypothalamic peptide that signals the pituitary to release GH. The analog is engineered with stabilizing modifications that resist enzymatic degradation. When it binds GHRH receptors on pituitary somatotrophs, it triggers GH release through the standard physiological pathway.

Ipamorelin is a small synthetic pentapeptide that activates the ghrelin receptor (GHS-R) on pituitary cells. Ghrelin signaling normally increases hunger and stimulates GH release; ipamorelin selectively activates the GH-release component while leaving appetite signaling largely alone. Combined with CJC-1295's GHRH activity, the result is amplified pulsatile GH release that the body's negative-feedback systems can still modulate — preserving the natural rhythm of secretion rather than overwhelming it.

The downstream effects of increased pulsatile GH are mediated largely through IGF-1 (insulin-like growth factor-1) elevation: lean mass support, fat loss, possibly improved sleep architecture, possibly enhanced recovery from training or injury.

Evidence, benefits, and side effects

Evidence tier: 2 — references summarized in the body; see Trial readouts section below for primary-source detail.

Evidence base in humans is limited compared to GLP-1s but real. CJC-1295 has been characterized in pharmacokinetic studies; ipamorelin has been tested in clinical trials for postoperative ileus. The combination in the doses used by the biohacker community has not been studied in formal RCTs; effects rest on mechanism, individual peptide data, and aggregated user reports.

Reported benefits at typical doses (8–16 week cycles):

• Improved sleep depth and architecture (most consistently reported).
• Modest body composition changes — lean mass slight up, fat mass slight down.
• Subjective recovery improvements after training or injury.
• Reported skin and connective tissue effects.

Effect sizes on body composition tend to be modest at typical doses, requiring months of consistent use. Bodybuilding-forum expectations frequently exceed the clinical reality.

Side effects:

• Injection-site reactions (common, mild).
• Tingling sensations or flushing shortly after dosing (common with ipamorelin specifically).
• Increased water retention.
• Mild fatigue or grogginess on initial doses.
• Theoretical concerns: chronic supraphysiologic GH/IGF-1 elevation could increase insulin resistance, accelerate undiagnosed malignancy, or promote benign prostatic hyperplasia in older men. Avoid in active cancer, uncontrolled diabetes, pregnancy, lactation. WADA-prohibited for competitive athletes.

Practical considerations

Evidence tier: 5 — community-evolved dose-range guidance; not RCT-derived.

• Form selection. No-DAC CJC-1295 + ipamorelin, dosed 2–3 times daily before meals or sleep, is the most common protocol. With-DAC dosing simplifies administration but produces tonic rather than pulsatile GH elevation, which may be less desirable physiologically.
• Dosing. Common protocol: 100–200 µg of each peptide, subcutaneously, 1–3 times daily.
• Cycling. 8–16 week cycles with 4-week breaks are typical to preserve receptor sensitivity.
• Legal. Both peptides are FDA Category 2 — compounding pharmacies cannot legally dispense in the US. Reclassification pending July 2026 PCAC review.
• Athletes. Both are WADA-prohibited under S2.

Where to go from here

For the broader Sleep & GH pillar including sermorelin and other secretagogues, see the goal-based hub. For per-state legal status, see the legal status guide.

Related on Peptide Story

• Sleep & GH pillar — growth-hormone-axis peptides
• CJC-1295 vs Sermorelin — GHRH analog comparison
• Sermorelin — peptide fact box

References

• Teichman S.L. et al. 2006. Prolonged stimulation of growth hormone and IGF-I by CJC-1295 in healthy adults. J Clin Endocrinol Metab.
• Raun K. et al. 1998. Ipamorelin, the first selective growth hormone secretagogue. Eur J Endocrinol.