READER QUESTIONS / EVIDENCE ANSWERS
The GH-Axis FAQ
Concise answers that keep receptor, population, endpoint, and uncertainty attached.
What is sermorelin?
Sermorelin is a synthetic version of the first 29 amino acids of human growth hormone-releasing hormone. It activates GHRH receptors on pituitary cells, prompting the body’s own growth-hormone release. Human studies document endocrine response in healthy men, children with GH deficiency, and a small older-men group [5][6][7]. Those findings do not establish sermorelin as an anti-aging treatment.
What does sermorelin do to the body?
Its direct documented action is to stimulate pituitary GH release, which can raise downstream IGF-1. Because that signal passes through the pituitary, feedback controls remain involved. A short study in older men found higher daily GH and IGF-1 measures without a fasting-glucose change during the study window [7]. Longer-term wellness outcomes and safety are not established.
Does sermorelin work?
It depends on the endpoint. Sermorelin clearly stimulated GH release in human pharmacology work [6], supported growth in children with GH deficiency [5], and raised GH-axis measures in a small older-men study [7]. Evidence does not establish that it prevents or reverses aging; an editorial concluded that secretagogues were not ready for that use [3].
How quickly were sermorelin effects measured in studies?
Timing varies by endpoint. In a healthy-volunteer pharmacology study, GH remained elevated for roughly three hours after intravenous GHRH(1-29) [6]. An older-men study evaluated repeated exposure over 14 days [7], while pediatric growth was assessed across the first treatment year [5]. Those observation windows describe research measurements, not a recommended schedule or expected personal result.
What is tesamorelin?
Tesamorelin is a stabilized 44-amino-acid GHRH analogue. It is an approved prescription medicine for reducing excess abdominal fat in adults with HIV-associated lipodystrophy [9]. Its evidence base includes randomized trials and a pooled analysis in that defined population [8][10][12]. Approval for one indication does not establish general weight-loss or anti-aging use.
How does tesamorelin work?
Tesamorelin activates pituitary GHRH receptors, increasing pulsatile endogenous GH release and downstream IGF-1. In a short study of healthy men, overnight GH and IGF-1 rose while fasting glucose and measured insulin-stimulated glucose uptake did not significantly change [11]. The mechanism helps explain fat-compartment research but does not guarantee the same outcome in unstudied populations.
Does tesamorelin reduce belly fat?
Trials support a reduction in visceral abdominal fat in adults with HIV-associated lipodystrophy. A pooled analysis of five randomized studies and individual clinical trials reported significant visceral-fat reductions [8][10][12]. The evidence is population-specific, and one longer program found reaccumulation after discontinuation [12]. It should not be reframed as a general abdominal-weight-loss promise.
What is CJC-1295?
CJC-1295 is a modified GHRH analogue. The long-acting DAC version binds albumin, extending exposure, while a no-DAC form is shorter acting. Human studies measured sustained GH and IGF-1 elevation and preserved GH pulses [15][16]. The record is early pharmacology, not proof of anti-aging, muscle, recovery, or fat-loss outcomes.
Is CJC-1295 proven safe?
No long-term human safety database in the composed evidence supports that conclusion. Early healthy-adult studies measured multi-day GH and IGF-1 changes [15][16], but they were not large or long enough to resolve chronic metabolic, fluid-balance, growth-signaling, or cardiovascular questions. The compound has no approved human indication, and DAC/no-DAC naming confusion further complicates interpretation.
Is there an established CJC-1295 human regimen?
This digest does not provide human dosing. Published early studies administered defined amounts under research protocols to characterize pharmacology [15][16]; those designs are not treatment recommendations. CJC-1295 has no approved human indication, and informal schedules are not substitutes for controlled evidence—especially when the DAC and no-DAC forms have very different persistence.
What is ipamorelin?
Ipamorelin is a five-residue growth-hormone secretagogue that activates the ghrelin receptor, GHS-R1a. Human pharmacology work found a short terminal half-life and a discrete GH pulse [20]. It differs mechanistically from GHRH analogues, and it is not an approved medicine. Human outcomes evidence is sparse.
What are the main evidence gaps and risks for ipamorelin?
The main gap is long-term human data. A postoperative Phase 2 study missed its primary endpoint [19], while several findings come from animals [17][21]. A different GHS-R1a agonist produced myocardial injury signals in a repeated-dose rat study; that is a class caution, not an ipamorelin-specific finding [18]. Appetite, fluid balance, glucose regulation, product identity, and chronic GH-axis exposure remain unresolved concerns.