CJC-1295 vs IGF-1 LR3
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 profileIGF-1 LR3
IGF-1 LR3 (Long Arg3 IGF-1) is a synthetic analogue of Insulin-like Growth Factor 1 with an amino acid substitution at position 3 and a 13-amino acid N-terminal extension. These modifications prevent binding to IGF-binding proteins (IGFBPs), dramatically extending its half-life from ~12 minutes (native IGF-1) to approximately 20–30 hours. IGF-1 LR3 is widely used in research for its ability to promote cellular growth, protein synthesis, hyperplasia, and nutrient uptake into muscle tissue.
Full profile| CJC-1295 | IGF-1 LR3 | |
|---|---|---|
| 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 | Insulin-like Growth Factor-1 Long R3, Long R3 IGF-1, Increlex (human equivalent) |
| Evidence | Research-stage | Research-stage |
| Dosing range | 100mcg–300mcg mcg, once daily (Mod GRF) or twice weekly (DAC version) | 20mcg–100mcg mcg, Once daily post-workout, on training days only (common protocol) |
| Administration | Subcutaneous injection (most common), Intramuscular injection | Subcutaneous injection, Intramuscular injection (into the trained muscle — site-specific protocols) |
| Key side effects | Water retention (especially early in protocol), Tingling or numbness in extremities, Injection site redness, Flushing (transient, shortly after injection) | Hypoglycemia (clinically significant — monitor blood sugar carefully), Jaw and organ growth with chronic high-dose use (theoretical at research doses), Fatigue and headaches, Joint pain |
| Cited sources | 2 references | 3 references |
Key differences
- Administration: CJC-1295 — Subcutaneous injection (most common), Intramuscular injection; IGF-1 LR3 — Subcutaneous injection, Intramuscular injection (into the trained muscle — site-specific protocols).
- Frequency: CJC-1295 is typically once daily (Mod GRF) or twice weekly (DAC version); IGF-1 LR3 is Once daily post-workout, on training days only (common protocol).
- Research depth: this profile cites 2 sources for CJC-1295 vs 3 for IGF-1 LR3.
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.
IGF-1 LR3
In vitro and animal research establishes IGF-1 LR3 as a potent anabolic and growth-promoting agent. It activates the IGF-1 receptor (IGF-1R) and downstream PI3K/Akt and MAPK/Erk pathways, promoting skeletal muscle hypertrophy and satellite cell activation. Its extended half-life makes it far more active systemically than native IGF-1. Research also documents its role in connective tissue repair, nerve regeneration, and fat oxidation. Human research is limited — most data comes from cancer cell biology and athletic performance settings.
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.