Growth hormone secretagogue is a loose label for compounds that prompt the pituitary to release growth hormone. Ranking pages lump them together, and that hides a real split in how they work and whether they are peptides at all. We read the drug labels, the trial abstracts and the vendor catalogs to sort them. This is not advice to use anything, and vendors label what they sell for laboratory research only.
The two doors to growth hormone release
Two receptors on the pituitary lead to growth hormone release. One is the growth hormone releasing hormone receptor. The tesamorelin label says the drug binds growth hormone releasing factor receptors and stimulates the release of the body's own growth hormone. The other is the growth hormone secretagogue receptor, also called the ghrelin receptor. The label for macimorelin says it stimulates release by activating those receptors in the pituitary and hypothalamus. A 1998 paper says ipamorelin acts through a GHRP-like receptor.
Three classes
Swipe the table sideways to see every column.
| Class | Examples | Receptor | Peptide? | Regulatory status we read |
|---|---|---|---|---|
| GHRH analogs | Sermorelin, tesamorelin, CJC-1295 | Growth hormone releasing hormone receptor | Yes | Egrifta WR (tesamorelin) is FDA-labeled for excess abdominal fat in HIV-infected adults with lipodystrophy. Our sermorelin vs tesamorelin post covers the rest. |
| Peptide secretagogues (GHRPs) | Ipamorelin, GHRP-2, GHRP-6, hexarelin | Secretagogue (ghrelin) receptor | Yes | We found no approved product. The FDA lists ipamorelin acetate in category 2 for outsourcing facilities. |
| Non-peptide ghrelin mimetics | MK-677 (ibutamoren), anamorelin, macimorelin | Secretagogue (ghrelin) receptor | MK-677 and anamorelin are described as non-peptide | Macrilen (macimorelin) is FDA-labeled to diagnose adult growth hormone deficiency. The FDA lists ibutamoren in category 2. |
What the trials measured
For the GHRH analogs, the trials we found measured hormone levels, visceral fat and growth in children. A 2006 trial of long-acting CJC-1295 in healthy adults raised growth hormone 2 to 10 fold and IGF-I 1.5 to 3 fold and reported nothing on muscle. A hormone level is a measurement of the hormone. Our posts on CJC-1295 and ipamorelin and on the best peptides for muscle growth cover those.
The only muscle-related results are for two non-peptide ghrelin mimetics, and they match. In a 2008 trial of 65 healthy adults aged 60 to 81, MK-677 raised fat-free mass 1.1 kg over a year against a 0.5 kg fall on placebo, and strength and function did not change. In the two ROMANA phase 3 trials of anamorelin in 979 people with lung cancer and cachexia, lean body mass rose over 12 weeks (0.99 kg against a 0.47 kg fall in one trial, 0.65 kg against a 0.98 kg fall in the other) while handgrip strength did not differ from placebo. Both are mass without a strength gain, in older adults and in people with advanced cancer. Neither is a trial in healthy lifters.
What the labels and the FDA record as risks
The tesamorelin label lists raised IGF-1, glucose intolerance, fluid retention and neoplasm risk among its warnings. The macimorelin label warns of QT prolongation, which can lead to a dangerous heart rhythm, and it is used as a single diagnostic test and not as an ongoing treatment. The MK-677 trial reported higher fasting glucose, lower insulin sensitivity and higher cortisol, and the FDA cites a hip fracture trial of ibutamoren that stopped early over a possible heart failure signal.
What the vendors list
All four vendors we review list the GHRH analogs and ipamorelin. We checked the whole Core Power Peptides shop, 102 product pages, and the product sitemaps for Peptides for Sale and Peptryn (), and the 82-page sitemap for American Peptides (). None lists GHRP-2, hexarelin, MK-677, macimorelin or anamorelin, and none lists GHRP-6 on its own. American Peptides lists one CJC-1295 blend that includes GHRP-6. Core Power Peptides and Peptides for Sale also list growth hormone fragments such as AOD-9604, which a 2026 review treats as a separate group from the secretagogues. Our guide to reading a COA and the reviews of Peptryn, Core Power Peptides and Peptides for Sale cover the paperwork.
Sports status
The Cologne anti-doping laboratory's page on the 2026 WADA Prohibited List names growth hormone releasing hormone analogs and growth hormone secretagogues and their mimetics, including ipamorelin, ibutamoren, macimorelin and anamorelin. Tested athletes should read the current list themselves.
Frequently asked questions
What is a growth hormone secretagogue?
A compound that prompts the pituitary to release growth hormone. Some act on the growth hormone releasing hormone receptor and others on the ghrelin receptor, and they are not all peptides.
Is MK-677 a peptide?
No. A 2001 paper calls ibutamoren a nonpeptide growth hormone secretagogue, and a 2008 trial calls it an oral ghrelin mimetic. Many ranking pages still list it with peptides.
Did any secretagogue trial show a strength gain?
Not in the two we found that measured it. MK-677 and anamorelin raised fat-free or lean mass in older adults and in cancer patients, and strength did not change or differ from placebo.