# Ipamorelin FAQ: Selectivity, Safety, CJC-1295 & More > Ipamorelin questions answered with citations: what it is, whether it is selective, safety, appetite, IGF-1, the CJC-1295 combination, and half-life. Never FDA-approved. Direct, cited answers to the questions people actually ask about ipamorelin — selectivity, safety, the CJC-1295 pairing, and more. ## What is ipamorelin? Ipamorelin (Aib-His-D-2-Nal-D-Phe-Lys-NH2) is a synthetic pentapeptide that released GH potently in rat pituitary cells, anaesthetised rats, and conscious swine — swine ED50 2.3 nmol/kg versus 3.9 nmol/kg for GHRP-6 — yet did not raise ACTH or cortisol even at more than 200 times its GH ED50 [1]. That makes it the first selective growth hormone secretagogue. ## What does ipamorelin do for you? In studies, ipamorelin triggers a clean pulse of growth hormone by activating the ghrelin receptor (GHS-R1a), without meaningfully raising cortisol or prolactin [1]. In humans it produced a single GH pulse peaking about 40 minutes after dosing [2]. It has no approved human use, and its one Phase 2 trial missed its endpoint [3]; reported personal effects are anecdotal, not clinical. ## What is ipamorelin peptide? It is a wholly synthetic five-amino-acid peptide (molecular formula C38H49N9O5, ~711.85 Da) that acts as a selective agonist of the GHS-R1a ghrelin receptor [1]. Derived from GHRP-1, its D-form amino acids resist enzymatic breakdown. It is a ghrelin mimetic engineered to release GH selectively, and it has never been approved as a drug. ## How does CJC-1295 ipamorelin work? They engage two complementary pathways. Ipamorelin activates the ghrelin receptor (GHS-R1a) via a calcium cascade [1], while CJC-1295 is a GHRH analog acting on the GHRH receptor. Combining a GHRH signal with a GHRP produces GH peaks greater than the sum of the individual peaks [12], which is the mechanistic basis for the pairing. No controlled human trial of the combination exists. ## Is ipamorelin selective for growth hormone? Yes — selectivity is its defining feature. Ipamorelin released GH as potently as GHRP-6 but did not raise ACTH or cortisol above the GHRH baseline even at doses more than 200-fold above its GH ED50 in rats and swine [1]. This clean separation of GH release from stress-hormone output is why it was named the first selective growth hormone secretagogue. ## What are the risks of ipamorelin? The honest risk is uncharacterized long-term safety. Its only Phase 2 RCT (n=114, 7-day IV dosing) missed its primary endpoint but showed no specific safety signal in that short window [3]. A class-level cardiovascular signal exists: a related GHS-R1a agonist caused myocardial degeneration in rats over 28 days [6]. No long-term human safety database exists, and research-grade material has unverified purity. ## Does ipamorelin reduce belly fat? No human trial shows this. In a 2024 ferret study, intraperitoneal ipamorelin (1–3 mg/kg) reduced cisplatin-induced weight loss by about 24% via a peripheral mechanism [5]. Community reports occasionally describe a gradual leaner appearance over weeks, but these are anecdotal and confounded by diet and training [16]. There is no controlled human evidence for targeted fat reduction. ## What are the downsides of ipamorelin? Its biggest downside is the evidence gap: no approved indication, a failed Phase 2 endpoint (time to first tolerated meal 25.3 h vs 32.6 h placebo, p=0.15) [3], and no long-term human safety data. Add a class-level cardiotoxicity signal [6], unverified research-grade purity, and a WADA S2 ban in sport. Reported side effects like flushing and appetite are anecdotal. ## Why is ipamorelin being discontinued? Ipamorelin was never an approved drug to discontinue. Its clinical development for postoperative ileus stopped because the only published Phase 2 trial missed its primary endpoint (p=0.15), and no further trials followed [3]. Separately, in 2024 the FDA removed ipamorelin acetate from Category 2 of the interim 503A bulk-substances list, restricting compounding-pharmacy access. ## What does CJC-1295 and ipamorelin do? Together they aim to amplify GH release through two pathways. In rats, exogenous GHRH plus a GHRP produced GH peaks significantly greater than the sum of individual peaks — a synergistic response [12]. CJC-1295 supplies GHRH-receptor tone; ipamorelin supplies a selective GHS-R1a pulse [1]. This synergy is animal pharmacology, not human combination-efficacy data. ## Does ipamorelin increase IGF-1? Not reliably in short studies. In a 15-day rat bone-growth study, ipamorelin increased longitudinal bone growth dose-dependently with no measurable change in total IGF-1, IGFBPs, or bone turnover markers [4]. Downstream IGF-1 elevation is context- and duration-dependent; the GH pulse does not automatically translate into a sustained IGF-1 rise in the short rodent windows tested. ## How much CJC-1295 ipamorelin should I take? There is no validated human dose. Neither ipamorelin nor the CJC-1295 combination has an approved human dose or a controlled-trial dosing basis [3]. Published ipamorelin doses are research exposures in animals and a few human volunteers [2], not personal regimens, and ipamorelin is banned in sport (WADA S2). This site does not provide human dosing. ## Does CJC-1295 ipamorelin work? For raising GH on mechanism, the synergy is real in animals: GHRH plus a GHRP produces more-than-additive GH peaks [12], confirmed in genetic models where a GHRP needs GHRH present to act [14]. For any human clinical outcome, there is no controlled trial of the combination — so 'works' is supported by mechanism, not by efficacy data. ## How to reconstitute CJC-1295 ipamorelin 5mg? Ipamorelin is supplied as a lyophilized (freeze-dried) powder reconstituted with bacteriostatic water for research handling, then typically refrigerated because peptides degrade with heat and freeze-thaw [2]. This is general handling context, not a preparation recipe or dosing instruction for human use — there is no approved human preparation of either peptide. ## How long does ipamorelin stay in your system? In healthy human volunteers, ipamorelin had a terminal half-life of approximately 2 hours after IV dosing, with clearance of 0.078 L/h/kg [2]. The GH response is a single discrete pulse peaking about 40 minutes after dosing [2]. The peptide acts quickly and clears within hours; in rats, plasma clearance is roughly five-fold lower than GHRP-6. ## Does ipamorelin make you hungry? Some users report increased appetite, with a clear mechanism: ipamorelin activates the ghrelin receptor (GHS-R1a), and central ghrelin-receptor agonists activate hypothalamic appetite centers and induce feeding in animals [17]. Community accounts describe this as real but milder than with GHRP-6. No controlled human study quantifies appetite change at research-use exposures. ## Will I gain weight on ipamorelin? There is no human data to answer this. In mice, ipamorelin produced a small (~15%) body-weight increase with elevated fat-pad weight and leptin in both GH-deficient and GH-intact animals — partly a GH-independent effect [16]. Appetite stimulation via the ghrelin receptor is a plausible contributor [17]. Any weight change in people would be confounded by diet and training and is not established. ## Does ipamorelin increase appetite? It can, by mechanism. Ipamorelin acts on GHS-R1a, the ghrelin (hunger) receptor, and central administration of ghrelin-receptor agonists activates brain appetite centers and induces feeding in animal models [17]. Community reports describe an appetite bump that is generally milder than GHRP-6. The effect is mechanistically expected but not quantified in controlled human studies. ## What does ipamorelin peptide do? It selectively activates the GHS-R1a ghrelin receptor on pituitary cells, releasing a clean pulse of growth hormone without meaningfully raising cortisol or prolactin [1]. In humans this is a single GH pulse peaking around 40 minutes post-dose [2]. It has reproducible GH-releasing effects in animals but no approved human indication and a failed Phase 2 trial [3]. ## How long does it take for ipamorelin to work? Pharmacologically, fast. In humans the GH response is a single discrete pulse peaking about 40 minutes (0.67 h) after dosing, with a terminal half-life of roughly 2 hours [2]. That describes the acute hormonal response, not any longer-term outcome — there is no controlled human study establishing a timeline for the body-composition or recovery effects people anecdotally report. ## Does ipamorelin cause water retention? Mild water retention and puffiness are occasionally reported by users, typically in the first two to four weeks and described as milder than with older GHRP compounds — but these are anecdotal, not clinical findings. Mechanistically, GH excess is associated with sodium and water retention [6], so the report is plausible. No controlled human study has measured fluid balance at research-use exposures. ## Where to inject CJC-1295 ipamorelin? This site does not provide injection or administration instructions for human use. In the research literature, ipamorelin has been studied by intravenous, subcutaneous, intraperitoneal, and intranasal routes depending on the model [2][5], and subcutaneous is the dominant route in community use — but none of that constitutes guidance. Ipamorelin has no approved human preparation and is banned in sport under WADA S2. --- A forward-looking digest of what the ipamorelin literature actually measured — built around the peptide's selectivity, cited line by line, with nothing here dosed, prescribed, supplied, or sold.