# CJC-1295 GH IGF-1 Axis: How It Raises Growth Hormone and IGF-1 > The CJC-1295 GH IGF-1 axis explained: how a single dose raised mean GH ~46% and IGF-1 ~45% a week later, why pulsatility is preserved, how long the effect lasts, and what the ipamorelin pairing adds — cited. GHRH receptor, growth-hormone pulse, hepatic IGF-1 — a three-step chain the studies measured carefully. Here is how big the effect was, how long it lasted, and where the honest gaps are. ## How the chain works The CJC-1295 GH IGF-1 axis is a three-link chain, and the literature follows it link by link. CJC-1295 binds the GHRH receptor on anterior-pituitary somatotrophs; that activates Gs/cAMP/PKA signaling, which stimulates synthesis and pulsatile release of growth hormone; the growth hormone then reaches the liver, engages the GH receptor, and — through JAK2/STAT5 — drives production of insulin-like growth factor 1 (IGF-1) [2]. IGF-1 is the hormone that mediates much of growth hormone's downstream anabolic effect. What makes the long-acting analog interesting is timing. Native GHRH and short-acting analogs hit the receptor and clear within minutes; the DAC variant, anchored to albumin, keeps the receptor stimulated for days while still letting the pituitary fire in its natural pulses [3]. The result is a sustained lift in both growth hormone and IGF-1. ## What the research reports CJC-1295 does Here is what the literature reports, in numbers. A single 60 or 90 µg/kg subcutaneous dose in healthy young men raised basal growth hormone roughly 7.5-fold, mean growth hormone by about 46%, and IGF-1 by about 45% one week later, with the frequency and magnitude of pulsatile GH secretion unaltered [3]. Across a dose-ranging study, 30 or 60 µg/kg gave dose-dependent growth-hormone elevation for six days or more and IGF-1 elevation for nine to eleven days [1]. A serum-proteomic study in 11 healthy men added a finer detail: CJC-1295 shifted several plasma proteins, and an immunoglobulin/albumin-fragment signal correlated linearly with IGF-1 [5]. Downstream, IGF-1 drives skeletal-muscle protein synthesis via PI3K/Akt/mTOR signaling and suppresses atrophy pathways — the molecular route through which GH/IGF-1 stimulation is hypothesized to affect body composition [12]. "Hypothesized" is the operative word: the human axis data is solid, the human outcome data is absent. ## How Long Does CJC-1295 Stay in the Body? The CJC-1295 half life depends entirely on which form you mean. The DAC variant, covalently bound to serum albumin, has an estimated half-life of 5.8–8.1 days in healthy adults, and after multiple doses IGF-1 elevation persisted up to 28 days [1]. That is the multi-day species. The no-DAC form, "Modified GRF 1-29," lacks the albumin handle and is short-acting — a minutes-to-hours range reflecting native GHRH(1-29) clearance with the protease-resistant substitutions [1]. The full disambiguation is on the [DAC vs no-DAC (Modified GRF 1-29)](/dac-vs-no-dac) page. ## Does CJC-1295 and ipamorelin work? GHRH analogs and growth-hormone-releasing peptides act through distinct receptors and synergize: co-administration produces growth-hormone release greater than the sum of either alone [10]. That two-receptor synergy is the published rationale for [CJC-1295 and ipamorelin synergy](/gh-igf-axis). What the data covers is the acute growth-hormone and IGF-1 response, not long-term body-composition outcomes in healthy adults — there is no controlled trial of the specific combination for that. ## How does CJC-1295 affect IGF-1 levels? By raising growth hormone, CJC-1295 drives hepatic IGF-1 production. Single 30–60 µg/kg doses raised IGF-1 1.5- to 3-fold for nine to eleven days; after multiple doses IGF-1 stayed above baseline up to about 28 days [1]. A serum-proteomic signal correlated linearly with IGF-1, marking candidate biomarkers of axis activation [5]. This sustained IGF-1 elevation is also the source of the main theoretical safety question — see the [side effects and safety questions](/faq). ## What to expect when taking CJC-1295? The measured physiology in studies is elevated growth hormone and IGF-1 with preserved pulsatility [3]. Beyond those biomarkers, controlled long-term outcome data in healthy adults do not exist, so claims about body composition, recovery, or "anti-aging" outrun the evidence. A careful reader expects exactly what was measured — a hormonal shift on lab readouts — and treats everything past that as unproven. ## How much CJC-1295 / ipamorelin should I take? There is no validated human dose for the combination. Community "protocols" pair fixed microgram amounts of each, but these are not derived from controlled human trials; the published basis is only the acute two-receptor growth-hormone synergy seen with GHRH-plus-GHRP co-administration [10]. The doses that do appear in the literature are described on the [doses used in the studies](/dosage) page, framed as research doses rather than recommendations. ## What is CJC-1295 ipamorelin? It is a research pairing of a GHRH analog (CJC-1295) with a selective growth-hormone secretagogue (ipamorelin). Because the two act on different receptors, co-administration produces greater growth-hormone release than either alone [10] — the rationale behind the combination. It is a pharmacology pairing, not a product, and not a tested clinical regimen. --- A friendly daisy-field notebook on the CJC-1295 research — the GH and IGF-1 numbers walked through gently, the DAC-and-no-DAC difference drawn plainly, and the missing long-term human safety data left honestly blank; nothing here is a clinic, a prescription, or for sale.