// questions
Ipamorelin FAQ
Direct answers from the research record. Cited where there is a number. Honest where there is a gap.
Does ipamorelin increase IGF-1?
Sometimes, not always. Ipamorelin pulses growth hormone, which can raise IGF-1 over time. But in a 15-day rat bone study, total IGF-1 did not change even as bones grew [1]. In rats given ipamorelin with a steroid, IGF-1 did rise [9]. Short pulses may not move systemic IGF-1; sustained signaling can. Context-dependent.
Does ipamorelin build muscle?
No human trial shows it. The muscle signal is preclinical: ipamorelin raised maximum tetanic muscle tension in steroid-treated rats [3], and a 2026 review reports CJC-1295 plus ipamorelin improved tetanic tension in a mouse muscle-loss model [15]. Those are animal models of muscle loss, not muscle-building trials in healthy humans. Reported gains in communities are anecdote, not evidence.
Is ipamorelin good for bones?
In rats, the bone data is its strongest record. Ipamorelin at 18-450 microg/day raised the longitudinal bone growth rate dose-dependently (42 to 52 microm/day) [1], 0.5 mg/kg/day for 12 weeks raised bone mineral content [2], and 100 microg/kg counteracted steroid-induced bone loss roughly four-fold [3]. All preclinical. No human bone trial exists.
What is ipamorelin?
Ipamorelin is a synthetic five-amino-acid peptide (Aib-His-D-2-Nal-D-Phe-Lys-NH2) that activates the ghrelin receptor (GHS-R1a) on the pituitary to release a pulse of growth hormone [4]. Its defining trait is selectivity: it does this without raising cortisol or prolactin [4]. It was the first selective growth hormone secretagogue, and it is not an approved drug.
What does ipamorelin do for you?
In studies, it triggers a clean pulse of growth hormone [4] and, in rats, lengthens bone and raises bone mineral content [1][2]. In people, the controlled evidence is thin and the one efficacy trial failed [5]. There is no proven human benefit. What users report — sleep, recovery, leaner look — is anecdotal, on the effects page.
What is ipamorelin peptide?
Ipamorelin peptide is a wholly synthetic pentapeptide — a chain of five amino acids — that mimics ghrelin at the GHS-R1a receptor to release growth hormone [4]. It is not made by the human body. It was developed in the 1990s as the first selective growth hormone secretagogue and remains an unapproved research compound [4][5].
What are the risks of ipamorelin?
The honest risk is the unknown: there is no long-term human safety data. The one Phase 2 trial logged adverse events in 87.5% of the ipamorelin arm vs 94.8% on placebo over a short window, with no specific signal [5]. Class-level concerns include a rat cardiotoxicity signal for a related compound [19] and theoretical IGF-1/cancer and glucose effects. Details on the effects page.
Does ipamorelin reduce belly fat?
No human trial shows targeted fat loss. The freshest in vivo data is a 2024 ferret study where ipamorelin (1-3 mg/kg) cut chemotherapy-induced weight loss by about 24% — that is preventing wasting, not burning belly fat [14]. In mice it actually raised fat mass and leptin in some conditions [17]. Reported leaning-out is anecdotal and confounded by diet.
What are the downsides of ipamorelin?
The biggest downside is no proven human benefit and no long-term safety data [5]. Reported downsides from research use include a facial flush after injection, more hunger, mild water retention, tingling, dizziness, and a fading response over months — all anecdotal, on the effects page. Class-level cardiotoxicity in a related compound is a documented preclinical concern [19].
Why is ipamorelin being discontinued?
It was never a marketed drug to discontinue. Its clinical development stopped because the only Phase 2 trial — for postoperative ileus — missed its primary endpoint (time to first tolerated meal 25.3 h vs 32.6 h placebo, p=0.15) [5]. Separately, in 2024 the FDA tightened pharmacy-compounding access by removing it from a 503A bulk-substance category, narrowing legal supply.
What does CJC-1295 and ipamorelin do?
Together they push growth hormone by two routes: CJC-1295 (a long-acting GHRH analog) raises the baseline, ipamorelin (a ghrelin-receptor agonist) fires a pulse [4][12]. A 2026 review reports the pair improved muscle tetanic tension in a mouse model but stresses evidence is animal-only [15]. No controlled human trial tests the combination for any outcome.
How does CJC-1295 ipamorelin work?
Two receptors, two pathways. CJC-1295 acts on the GHRH receptor (a cAMP pathway) to sustain growth-hormone output; ipamorelin acts on GHS-R1a, the ghrelin receptor (a calcium pathway), to pulse it [4]. The pathways are complementary, which is the published rationale for pairing them [12]. The mechanism is well-described; combined human outcomes are not.
How much CJC-1295 ipamorelin should I take?
No controlled human trial established a dose for the combination, so this site cannot answer it. The human ipamorelin doses on record are an IV pharmacokinetic range and a 0.03 mg/kg IV surgical-trial dose [6][5]; the CJC-1295 human study used 30-60 microg/kg subcutaneously [12]. Community microgram routines have no peer-reviewed human dosing basis.
Does CJC-1295 ipamorelin work?
For raising growth hormone short-term, the single-agent evidence is real [4][12]. For physique or anti-aging outcomes, there is no controlled human trial of the combination — the strongest combination data is a mouse muscle-loss model in a 2026 review [15]. So the hormones move; the human outcomes are unproven.
How to reconstitute CJC-1295 ipamorelin 5mg?
As a handling note only: ipamorelin ships as a lyophilized (freeze-dried) powder and is reconstituted with bacteriostatic water for research handling, then kept refrigerated because peptides degrade with heat and freeze-thaw [6]. This is a general research-supply observation, not a clinical preparation method, and nothing here specifies an amount to give a person.
How long does ipamorelin stay in your system?
Not long. In healthy human volunteers the terminal half-life is about 2 hours (IV), with the growth-hormone pulse peaking near 40 minutes after dosing [6]. By the usual five-half-life rule, the peptide itself is largely cleared within about 10 hours. Detection windows for anti-doping testing differ, since metabolites can be measured in urine.
Does ipamorelin make you hungry?
Some users report yes, in the hours after a dose, which fits the mechanism — ipamorelin hits the ghrelin (hunger) receptor. In animals, ghrelin-receptor agonists activate brain appetite centers and drive feeding [16]. Community reports call the appetite bump milder than GHRP-6. There is no measured human appetite rate; the report is anecdotal.
Will I gain weight on ipamorelin?
No human data answers this. In mice, ipamorelin raised fat mass and leptin in some conditions, partly independent of growth hormone [17]. Some users report mild early water retention and increased appetite, anecdotally; others report a gradually leaner look. All of it is anecdotal and confounded by diet and training. There is no controlled human weight outcome.
Does ipamorelin increase appetite?
Mechanistically, plausibly yes. Ipamorelin is a ghrelin-receptor agonist, and ghrelin is the body's hunger hormone; in animals these agonists activate appetite centers and induce feeding [16]. Two weeks of ipamorelin also raised fat mass and leptin in mice [17]. Community reports describe the appetite effect as milder than GHRP-6 — but it is anecdotal, not a measured human rate.
What does ipamorelin peptide do?
Ipamorelin peptide activates the ghrelin receptor on the pituitary to release a selective pulse of growth hormone — without raising cortisol or prolactin [4]. In rats it lengthens bone and raises bone mineral content [1][2]. In humans, controlled benefit is unproven and its one efficacy trial failed [5]. It is a research peptide, not an approved drug.
How long does it take for ipamorelin to work?
Biochemically, fast: the growth-hormone pulse peaks near 40 minutes after a dose and the peptide clears with a ~2 hour half-life [6]. Any longer-term effect is a different question with no human answer — community reports of sleep changes cite one to two weeks, but that is anecdotal, not a measured onset from any trial.
Does ipamorelin cause water retention?
Some users report mild, transient puffiness — fingers, ankles, face — mostly in the first few weeks, described as milder than older peptides — anecdotally. Mechanistically, growth-hormone stimulation can hold sodium and water, so it is plausible. But there is no controlled human study measuring fluid retention with ipamorelin; the reports are anecdotal.