Definition
A secretagogue is any compound that causes a gland or cell to release a stored substance, typically a hormone. The word combines the Latin 'secretus' (to separate or set apart) with the Greek 'agogos' (leader or carrier) — literally a 'leader of secretion.' In peptide therapy, the term is used most often for growth hormone secretagogues: compounds that act on the pituitary gland (usually through the ghrelin receptor) to trigger the body's own pulsatile release of growth hormone, rather than introducing exogenous growth hormone itself. Ipamorelin is the most common growth hormone secretagogue referenced across TruthTides — it stimulates GH release from the pituitary without significantly affecting cortisol or prolactin levels, and is frequently combined with the GHRH analog CJC-1295 for synergistic growth hormone optimization. Outside of growth hormone, the broader pharmacology literature also uses 'secretagogue' for insulin secretagogues (such as sulfonylureas, which trigger insulin release from pancreatic beta cells) and gastric acid secretagogues — but on this site the term almost always refers to growth-hormone-releasing peptides.
Source: Ipamorelin peptide summary, CJC-1295 comparison table, and GHRH peptide profiles
Frequently Asked
What is a secretagogue?
A secretagogue is a compound that causes a gland or cell to secrete (release) something it already produces — most commonly a hormone. It does not replace the hormone itself; it tells the body to release more of its own. In peptide therapy, the word almost always refers to growth hormone secretagogues, which signal the pituitary gland to release the body's own growth hormone.
What are secretagogues used for in peptide therapy?
In peptide therapy, secretagogues are used primarily to optimize the body's natural growth hormone output. Ipamorelin is the most widely referenced example on TruthTides — it acts on the ghrelin receptor in the pituitary to trigger pulsatile GH release without significantly affecting cortisol or prolactin. It is frequently combined with CJC-1295 (a GHRH analog) so the two compounds amplify each other through complementary pathways. None of these growth hormone secretagogues are FDA-approved; access in the U.S. is typically through 503A compounding pharmacies under physician supervision.
What is the difference between a secretagogue and a GHRH analog?
Both raise growth hormone, but they act on different receptors. GHRH analogs like CJC-1295, Sermorelin, and Tesamorelin mimic growth hormone-releasing hormone and bind the GHRH receptor on the pituitary. Secretagogues like Ipamorelin bind the ghrelin (GHS-R) receptor on the same gland. Because the two pathways are independent, combining a GHRH analog with a secretagogue (commonly CJC-1295 + Ipamorelin) produces a larger GH pulse than either alone.
Are growth hormone secretagogues FDA-approved?
Ipamorelin and most other growth hormone secretagogues are not FDA-approved drugs in the United States. They are typically prepared by 503A compounding pharmacies for individual patient prescriptions written by a licensed practitioner. Tesamorelin (a GHRH analog, not a true secretagogue) is the FDA-approved peptide in this broader category — approved as Egrifta for HIV-associated lipodystrophy.
Is a secretagogue the same thing as growth hormone?
No. A secretagogue is not growth hormone — it is a signal that tells your pituitary to release the growth hormone your body already makes. This is mechanistically different from injecting recombinant human growth hormone (rHGH), which introduces exogenous hormone directly. Secretagogue protocols rely on the body's own pulsatile release pattern, which is why dosing is usually timed around sleep or fasted states.