Growth hormone secretagogues

These compounds make the pituitary release more of the body’s own growth hormone, through one of two receptors: the GHRH receptor or the ghrelin receptor. Tesamorelin is the only one approved as a treatment, and most of the others rely on small or short studies.

Compounds: 11
Approved drug: 2
Human studies: 6
Preclinical: 1
Blends: 2

Members

GHRH analogs

Copies of growth-hormone-releasing hormone. Tesamorelin is approved; sermorelin was, for children, until 2008; CJC-1295 never has been.

Compound	What it is	Approval	Evidence	How often	Half-life	Sport
Sermorelin	GHRH analog	Formerly approved in the US	Human studies	Once nightly	about 6 to 7 minutes Label	Banned
Tesamorelin	GHRH analog	Approved in the US	Approved drug	Once daily	about 8 to 11 minutes Label	Banned
CJC-1295 (no DAC)	GHRH analog	Not approved	Preclinical	1–3× daily (bedtime most common)	Not measured	Banned
CJC-1295 with DAC	Long-acting GHRH analog	Not approved	Human studies	Once weekly	about 6 to 8 days Trial	Banned

Ghrelin-receptor agonists

Mimic ghrelin, the hunger hormone. MK-677 is a pill, not a peptide, and GHRP-2 is approved only as a one-time diagnostic test in Japan.

Compound	What it is	Approval	Evidence	How often	Half-life	Sport
Ipamorelin	Ghrelin-receptor agonist (GHRP)	Not approved	Human studies	1–3× daily (bedtime most common)	about 2 hours Trial	Banned
GHRP-2	Ghrelin-receptor agonist (GHRP)	Approved outside the US	Approved drug	1–3× daily (morning and bedtime are common)	about 25 to 40 minutes Label	Banned
GHRP-6	Ghrelin-receptor agonist (GHRP)	Not approved	Human studies	2–3× daily	about 2.5 hours Trial	Banned
Hexarelin	Ghrelin-receptor agonist (GHRP)	Not approved	Human studies	1–2× daily (twice daily is common)	Not measured	Banned
MK-677	Ghrelin-receptor agonist (oral GH secretagogue)	Investigational	Human studies	Once daily	Not measured	Banned

Blends

One of each type, premixed. Neither blend, nor either pairing, has been studied.

Compound	What it is	Approval	Evidence	How often	Half-life	Sport
CJC-1295 + Ipamorelin	GH secretagogue blend	Blend	Blend	Once nightly	See each part	Banned
Tesamorelin + Ipamorelin	GH secretagogue blend	Blend	Blend	Once daily	See each part	Banned

Approval, evidence, half-life and sport status restate each compound’s own page, where the sources are listed. Select a name for doses, side effects and studies.

How they work

Growth hormone (GH) comes from the pituitary, a gland at the base of the brain, in pulses. Growth-hormone-releasing hormone (GHRH), sent from the hypothalamus, the brain area that controls the pituitary, switches release on, and somatostatin switches it off. GH builds tissue and breaks down fat, partly by prompting the liver to make IGF-1, a growth factor. Every member of this group pushes the body’s own GH release rather than replacing GH. Label

There are two routes in. GHRH analogs (sermorelin, tesamorelin and both forms of CJC-1295) act on the GHRH receptor on the pituitary. Ghrelin-receptor agonists (ipamorelin, GHRP-2, GHRP-6, hexarelin and MK-677) act on the receptor for ghrelin, the hunger hormone, in the hypothalamus and on the pituitary. In small human studies, natural GHRH given with GHRP-6, hexarelin or GHRP-2 released more GH than either alone, the logic behind the blends; the blends themselves have never been tested. Trial

Most give a short pulse. After an IV dose of sermorelin, GH peaked at about 30 minutes and lasted 2–3 hours, and after IV ipamorelin it peaked at about 40 minutes and was back to very low levels within 6 hours. Two were built to last: CJC-1295 with DAC binds albumin, a blood protein, and one injection raised GH for 6 days or more, while one daily dose of MK-677, a pill, kept GH and IGF-1 raised in trials. Trial

In people, the clearest results are hormone changes. Tesamorelin cut belly fat in adults with HIV in 26-week trials, the basis of its approval, and the fat came back within months of stopping. MK-677 added about 1 kg of lean mass over 2 years in healthy older adults, without gains in strength or function. The GH response to GHRP-6 and hexarelin faded with constant or daily use. Trial

What they have in common

Higher blood sugar

Label

Growth hormone raises blood sugar. Tesamorelin’s label warns it can cause glucose intolerance or diabetes and says to check glucose before and during treatment. MK-677 raised fasting glucose in trials, high blood sugar was more common on ipamorelin in an IV trial, and FDA lists diabetes among the risks of drugs that raise GH.

Fluid retention and joint pain

Label

Tesamorelin’s label lists fluid retention, with swelling, joint pain and carpal tunnel syndrome (numb, tingling hands), and links it to the rise in GH. On MK-677, leg swelling affected 19 of 43 people vs 6 of 22 on placebo over 2 years. The compound pages report the same pattern for the unapproved members.

Cancer and who should avoid them

Label

Tesamorelin’s label rules out active cancer, pregnancy and a damaged pituitary (after surgery, a tumor, head radiation or trauma). The other members lack such labels, but they raise the same hormones, so their pages list active or past cancer, diabetes and pregnancy as precautions. No trial was designed to test cancer risk.

Combining members

Precaution

Two GHRH analogs, or two ghrelin-receptor agonists, act on the same receptor and double up rather than add; the stack check flags both. One of each is the usual pairing, as in the two blends, but neither blend has been studied, and CJC-1295 or tesamorelin has never been tested with ipamorelin.

Banned in sport

WADA bans the whole group at all times under S2.2.4, growth hormone releasing factors, which names sermorelin, tesamorelin, CJC-1295, ipamorelin, GHRP-2 (pralmorelin), GHRP-6, hexarelin (as examorelin) and ibutamoren (MK-677).

Evidence across the group

Trial

Thin outside one approval. Tesamorelin rests on 26-week trials in about 800 adults with HIV. Sermorelin’s approval was for children and ended in 2008, GHRP-2’s covers a one-time diagnostic test in Japan, and MK-677 has placebo-controlled trials of up to 2 years. CJC-1295 without DAC has no published study at all.

How they differ

Receptor and structure

Sermorelin, tesamorelin and both CJC-1295s act on the GHRH receptor: tesamorelin is a stabilized copy of the full 44-amino-acid hormone, and the others are built on its first 29. Ipamorelin, GHRP-2, GHRP-6 and hexarelin are 5- and 6-amino-acid peptides acting on the ghrelin receptor, and MK-677 is a small molecule.

How long a dose lasts

Trial

Sermorelin and tesamorelin clear from the blood in minutes and GHRP-2 in under an hour; ipamorelin’s half-life is about 2 hours and GHRP-6’s about 2.5. CJC-1295 with DAC lasts about 6–8 days and is injected weekly, and MK-677 is taken once a day. CJC-1295 without DAC has never been measured.

Side effects that differ

Trial

Ghrelin-receptor agonists raise hunger: healthy men ate 36% more during a GHRP-2 infusion, and strong hunger is GHRP-6’s most reported effect. GHRP-6 and hexarelin also raise cortisol and prolactin, a pituitary hormone, while ipamorelin didn’t raise cortisol in animal studies. MK-677 brought a heart-failure signal in frail older adults. GHRH analogs mainly cause flushing and injection-site reactions.

Form and dosing frequency

Community

All are injected except MK-677, taken by mouth. Tesamorelin is injected daily into the belly, per its label. Community use runs sermorelin nightly, the short-acting ghrelin-receptor peptides and CJC-1295 without DAC 1–3 times a day, and CJC-1295 with DAC weekly. The blends are dosed by one component’s share.

Approval

Tesamorelin is FDA-approved (Egrifta WR and Egrifta SV) only to reduce excess belly fat in adults with HIV-associated lipodystrophy. GHRP-2 is approved in Japan only as a single IV diagnostic dose. Sermorelin (Geref) was approved for children with GH deficiency until it was discontinued in 2008. The others, and both blends, are approved nowhere.

History

1982GHRH, a 44-amino-acid peptide, was isolated from a pancreatic tumor that had caused acromegaly, the overgrowth disorder driven by excess GH.
1984A synthetic six-amino-acid peptide, later known as GHRP-6, was shown to act on the pituitary to release GH specifically.
1990FDA approved sermorelin (Geref) as a diagnostic test; a 1997 approval added treatment of GH deficiency in children.
1996The receptor that GHRP-6 and similar compounds act on was cloned from pituitary and hypothalamus; in 1999 its natural hormone, ghrelin, was found in the stomach.
2010FDA approved tesamorelin (Egrifta) to reduce excess belly fat in adults with HIV-associated lipodystrophy.

Comparisons and guides

Questions

What are growth hormone secretagogues?

Compounds that make the pituitary release more of the body’s own growth hormone instead of supplying GH itself. GHRH analogs such as sermorelin, tesamorelin and CJC-1295 copy the brain’s GH-release signal; ghrelin-receptor agonists such as ipamorelin, the GHRPs and MK-677 mimic ghrelin, the hunger hormone. Both routes raise GH and, in turn, IGF-1.

Which growth hormone secretagogues are approved?

Only tesamorelin is an approved treatment: as Egrifta WR and Egrifta SV, to reduce excess belly fat in adults with HIV-associated lipodystrophy. GHRP-2 is approved in Japan as a single IV test dose for GH deficiency. Sermorelin was approved in the US for children with GH deficiency until 2008; FDA later found it wasn’t withdrawn for safety or effectiveness reasons.

Is MK-677 a peptide?

No. MK-677 (ibutamoren) is a small molecule taken by mouth that mimics ghrelin at its receptor. One daily dose kept GH and IGF-1 raised in trials of up to 2 years, but it raised blood sugar, and a hip-fracture trial in older adults was stopped early over heart failure (4 of 62 vs 1 of 61 on placebo). It isn’t approved anywhere.

Why is CJC-1295 paired with ipamorelin?

They act on different receptors, CJC-1295 on the GHRH receptor and ipamorelin on the ghrelin receptor, and in small human studies natural GHRH plus GHRP-6, hexarelin or GHRP-2 released more GH than either alone. That has never been shown for CJC-1295 with ipamorelin: the pairing has no published trial, and CJC-1295 without DAC has none on its own either.

Are growth hormone secretagogues banned in sport?

Yes. WADA’s 2026 list bans growth hormone releasing factors at all times, in and out of competition, under S2.2.4. It names sermorelin, tesamorelin, CJC-1295, ipamorelin, GHRP-2 (pralmorelin), GHRP-6, hexarelin (as examorelin) and ibutamoren (MK-677).

Sources

Egrifta WR and Egrifta SV prescribing information, sections 4, 5 and 12 (DailyMed, rev. 07/2026); Drugs@FDA approval of Egrifta, November 2010
Former Geref (sermorelin) labels: US prescribing information (Serono, rev. 10/2001) and Irish Geref 50 summary of product characteristics; Drugs@FDA approvals, December 1990 and September 1997
Guillemin et al., growth hormone-releasing factor from a human pancreatic tumor that caused acromegaly (Science 1982) PMID 6812220
Bowers et al., a new synthetic hexapeptide that acts on the pituitary to release growth hormone (Endocrinology 1984) PMID 6714155
Howard et al., a receptor in pituitary and hypothalamus that functions in growth hormone release (Science 1996) PMID 8688086
Kojima et al., ghrelin, a growth-hormone-releasing acylated peptide from stomach (Nature 1999) PMID 10604470
Bowers et al., GH-releasing peptide acts synergistically with GHRH in normal men (J Clin Endocrinol Metab 1990) PMID 2108187
Teichman et al., prolonged GH and IGF-1 rise after CJC-1295 in healthy adults (J Clin Endocrinol Metab 2006) PMID 16352683
Nass et al., 2-year trial of MK-677 in healthy older adults (Ann Intern Med 2008) PMID 18981485
FDA briefing documents on ipamorelin and ibutamoren (MK-677), Pharmacy Compounding Advisory Committee (October 2024)

Each compound’s page lists the sources for its own doses, status and studies.

By Vial Guide editorsLast reviewed October 7, 2026

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