CJC-1295 vs Melanotan II
A neutral, side-by-side comparison of two performance & growth hormone peptides — their mechanisms, dosing ranges, administration routes, side effects, and research evidence. For research and educational purposes only.
CJC-1295
CJC-1295 is a synthetic growth hormone-releasing hormone (GHRH) analog. It stimulates the pituitary gland to release growth hormone and is almost universally used in combination with a GHRP like Ipamorelin to produce a more physiological GH pulse.
Full profileMelanotan II
Melanotan II (MT-II) is a cyclic lactam analog of alpha-melanocyte stimulating hormone (α-MSH) that acts as a potent, non-selective melanocortin receptor agonist (MC1R, MC3R, MC4R, MC5R). Developed at the University of Arizona in the late 1980s, it produces eumelanin-driven skin darkening (tanning) via MC1R, sexual arousal and spontaneous erections via MC4R, and appetite suppression via MC3R/MC4R. Bremelanotide (PT-141) — now FDA-approved for female sexual dysfunction — was derived from Melanotan II.
Full profile| CJC-1295 | Melanotan II | |
|---|---|---|
| Category | Performance & Growth Hormone | Performance & Growth Hormone |
| Also known as | CJC-1295 DAC, CJC-1295 without DAC (Mod GRF 1-29), Modified GRF 1-29 | MT-II, MTII, Cyclo[Nle4,D-Phe7]-α-MSH |
| Evidence | Research-stage | Research-stage |
| Dosing range | 100mcg–300mcg mcg, once daily (Mod GRF) or twice weekly (DAC version) | 250mcg–1000mcg mcg, Daily during loading phase; 2–3x weekly for maintenance |
| Administration | Subcutaneous injection (most common), Intramuscular injection | Subcutaneous injection (most common), Intranasal (less effective, lower bioavailability) |
| Key side effects | Water retention (especially early in protocol), Tingling or numbness in extremities, Injection site redness, Flushing (transient, shortly after injection) | Nausea (most common — especially first 30–60 minutes post-injection), Facial flushing, Spontaneous erections (males — often unwanted at higher doses), Fatigue / yawning post-injection |
| Cited sources | 2 references | 3 references |
Key differences
- Administration: CJC-1295 — Subcutaneous injection (most common), Intramuscular injection; Melanotan II — Subcutaneous injection (most common), Intranasal (less effective, lower bioavailability).
- Frequency: CJC-1295 is typically once daily (Mod GRF) or twice weekly (DAC version); Melanotan II is Daily during loading phase; 2–3x weekly for maintenance.
- Research depth: this profile cites 2 sources for CJC-1295 vs 3 for Melanotan II.
How each works
CJC-1295
Studies have demonstrated that CJC-1295 significantly increases plasma GH and IGF-1 levels. The DAC (Drug Affinity Complex) version extends the half-life to approximately 6–8 days via albumin binding, while Mod GRF 1-29 has a much shorter half-life (~30 minutes) and is dosed more acutely. Research in adults with GH deficiency has shown improved body composition and metabolic markers.
Melanotan II
Melanotan II's broad melanocortin receptor agonism produces a constellation of effects across multiple systems. MC1R activation in melanocytes upregulates tyrosinase, the rate-limiting enzyme in melanin synthesis, producing UV-independent skin darkening. MC4R activation in the CNS and spinal cord drives sexual arousal and erectogenic effects more potent than most PDE5 inhibitors, and also produces appetite suppression and reduced food intake (the same pathway exploited by weight-loss drugs targeting the melanocortin system). MC3R activation contributes to energy homeostasis effects.
This comparison aggregates public research and structured profile data for informational purposes only. It is not medical advice and does not recommend either compound for human use. Consult a qualified healthcare provider before considering any peptide.