MK-677: Oral GH Secretagogue Map (Ibutamoren)

People type MK-677 like they found oral HGH in a capsule.

They found a ghrelin-receptor key you can swallow.

That is a real research file. It is not a steroid. It is not a weekly GH pen. It is not an FDA-approved muscle, sleep, or anti-aging drug. The nickname ibutamoren is the same molecule. Catalogs also write MK-0677. Same idea. Different sticker.

Why this matters right now: the GH lane on this site is already live for the injectables. Ipamorelin is the selective GHRP. CJC-1295 no DAC plus ipamorelin is the pulse pair. Tesamorelin is the GHRH analog with a visceral-fat drug file. MK-677 is the oral cousin on the ghrelin door. Stay here if that is the name you typed. Start with Start Here if peptides are not day one. The class hub is peptides for muscle growth.

This is education. It is not medical advice. It is not a reason to skip a clinician. It is not a buy-this-to-grow pitch. A research-catalog capsule is not a labeled GH drug.

What is MK-677, actually?

A secretagogue asks a gland to release a hormone. It does not replace the hormone in a syringe. MK-677 asks the pituitary for a GH pulse by copying ghrelin at the GH secretagogue receptor. That receptor also gets called GHS-R. Ghrelin is the stomach hormone people nickname hunger hormone. Merck built a swallowable copy of that knock in the 1990s.

Here is the format trap. Shops file MK-677 next to peptides. The molecule is not a peptide. A peptide is a short chain of amino acids. Ipamorelin is a peptide. CJC no DAC is a peptide. Tesamorelin is a peptide. MK-677 is a small-molecule spiropiperidine. You swallow it. You do not reconstitute it. Naming the shelf does not name the chemistry.

Howard and colleagues cloned that pituitary and hypothalamus receptor in Science in 1996. Kojima and colleagues named the natural ligand ghrelin in Nature in 1999. Smith’s group reviewed the peptidomimetic story in Endocrine Reviews in 1997. So what? The lock was found with a pill-shaped key before the body’s own key had a name. That is why MK-677 shows up in GH conversations that also include injectable secretagogues.

It is still not HGH. Recombinant GH is a replacement hormone. MK-677 is an ask. The gland has to be able to answer. Somatostatin still gets a vote. A dead somatotroph does not become a young one because you found a coupon code.

The wow analogy: two doors, one oral key

Think of the pituitary as a house with two front-door locks.

Lock one is the ghrelin receptor. Ghrelin knocks here. Ipamorelin knocks here with a needle. MK-677 knocks here with a swallow. Same lock. Different key shape. Different how-long-it-stays-in-the-tumbler story.

Lock two is the GHRH receptor. GHRH is growth-hormone-releasing hormone. That is the hypothalamic signal that already asks for a GH pulse. CJC-1295 no DAC is a pulse-length GHRH analog. Tesamorelin is still GHRH, with a labeled visceral-fat conversation behind the brand name Egrifta. Sermorelin is GHRH 1-29. People search it first. Experienced users on this site do not put it first. I will not crown it here either.

Why should you care? Because forums mash all five names into one “GH stack” caption. Two locks. One oral key. One injectable ghrelin key. Two GHRH keys worth mapping. One beginner search term. If you cannot name the lock, you are shopping a nickname.

MK-677 vs ipamorelin vs CJC no DAC vs tesamorelin

You do not need a fellowship. You need four jobs and one warning.

Lane	What it actually is	What the evidence talk is	What it is not
MK-677 / ibutamoren	Oral small-molecule GHS-R agonist. Ghrelin-receptor door. Once-daily swallow in the trials.	Human randomized files in older adults, short young-adult studies, a small sleep study, and hip-fracture programs that did not win function. Glucose and appetite show up in the same papers.	Not a peptide. Not a steroid. Not injectable ipamorelin in a capsule. Not FDA-approved for muscle, sleep, or aging.
Ipamorelin	Injectable pentapeptide GHS-R agonist. Same ghrelin door. Short pulse.	Selective GHRP map on ipamorelin. Different format. Different duration story.	Not MK-677. Not GHRH. Not a reason to skip the oral-versus-needle conversation.
CJC-1295 no DAC	Injectable GHRH analog. Mod GRF 1-29. Other door. Still a pulse.	Usually discussed next to ipamorelin as a two-door pair. Full map: CJC-1295 and ipamorelin.	Not MK-677. Not CJC with DAC. Not “oral CJC.”
Tesamorelin	Injectable GHRH analog. Visceral-fat literature. Egrifta is the FDA-labeled brand for a specific HIV-associated abdominal-fat indication.	Map on tesamorelin. A research vial does not inherit that label.	Not a GHRP. Not oral MK-677 for belly fat. Not a muscle-growth crown.
Sermorelin	GHRH 1-29. Short-acting analog. The name people Google first.	Older diagnostic and pediatric GH-deficiency file. Live page exists. It is the least-favorite GHRH analog in this GH lane on purpose.	Not the class winner. Not MK-677. Not a reason to start here if you actually meant the oral ghrelin key.

You can be interested in the oral ghrelin key and the injectable pair in the same month of reading. You cannot flatten them into one Reddit protocol and call a capsule a two-door stack.

Stop-you stat: fat-free mass moved. Function did not.

Why this matters: the caption sells “oral GH.” The trial sold a quieter sentence.

Nass, Thorner, and colleagues published a 2-year randomized, double-blind, placebo-controlled trial in the Annals of Internal Medicine in 2008. Sixty-five healthy adults. Ages 60 to 81. Oral MK-677 25 mg once daily, or placebo. Primary look at one year: growth hormone and IGF-I, fat-free mass, abdominal visceral fat. IGF-I is insulin-like growth factor I. It is the downstream marker clinicians use when they talk about the GH axis.

Stop-you stat: fat-free mass rose 1.1 kg on MK-677 and fell 0.5 kg on placebo. Body weight rose 2.7 kg versus 0.8 kg. Limb fat also rose more on the drug. Abdominal visceral fat did not show a significant group difference. Strength and function did not move with the extra fat-free mass. Fasting glucose rose an average of 0.3 mmol/L, which is about 5 mg/dL. Insulin sensitivity went the wrong way. Appetite went up, then often settled. Mild ankle swelling and muscle pain showed up. Cortisol ticked up a little. Two-year numbers confirmed the one-year shape.

How sure should you be? High confidence that this happened in that healthy older group under that protocol. Medium confidence that a 25-year-old lifter can paste the kilogram onto a research-catalog bottle. Low confidence that “1.1 kg fat-free mass” means a gym PR, a viscera melt, or a pass on blood sugar. The authors said the study was not powered to prove function. That is an honest limit. Keep it.

Chapman and colleagues ran an earlier four-week file in 32 healthy adults aged 64 to 81. At 25 mg a day, mean 24-hour GH almost doubled. Serum IGF-I went from 141 to 265 micrograms per liter by week four, into a young-adult band. Fasting glucose went from 5.4 to 6.8 mmol/L. That glucose move is the part forums skip. It is also in the abstract.

Evidence limits, stated plainly:

• Nass 2008 is a real 2-year randomized file in healthy older adults, not a gym-bro n of 12
• Fat-free mass can rise without strength or function rising
• Visceral fat was not the winner in that trial
• Chapman 1996 restored IGF-I and raised fasting glucose in the same month
• A research-catalog capsule is not the Merck trial product
• No FDA muscle, sleep, or anti-aging label lives on this page because none exists for this use

Appetite is the mechanism, not a side quest

MK-677 copies ghrelin. Ghrelin makes you hungry. Shocking, I know.

Nass reported an appetite increase that often faded over a few months. That is not a personality flaw. That is the receptor doing the job you asked it to do. If the caption promised “recomp without eating more,” the receptor did not read the caption.

Murphy and colleagues tested whether oral MK-677 could blunt diet-induced catabolism in a short calorie-restriction file in 1998. That is a research question about nitrogen and IGF-I under a cut, not a contest-prep protocol. How sure? One small clinical-physiology paper. Interesting. Not a free pass to under-eat and swallow a secretagogue.

Foolish read: if your actual job is hunger control, you are standing on the wrong hormone. GLP-1 drugs live on a different map. This page will not pretend a ghrelin agonist is an appetite-suppressant with extra steps.

Glucose is the caveat you do not get to skip

GH pushes back on insulin. That is old endocrinology, not a tweet.

Chapman’s 25 mg arm moved fasting glucose from normal-ish into a band clinicians watch. Nass saw a smaller average bump over a year, plus worse insulin sensitivity. Copinschi’s 7-day study in nine healthy young men mapped 24-hour GH pulses and IGF-I without turning cortisol into the headline. Different ages. Same axis. Same reason you talk to a clinician before you DIY a glucose experiment.

How sure are we? High that glucose signals show up across these files. Not a claim that every person becomes diabetic. Not a claim that MK-677 treats diabetes either. If you already watch A1C, fasting glucose, or a family history, this is a clinician conversation. This page will not write you a workaround.

Sleep: a real paper, a small paper

Copinschi, Van Cauter, and colleagues published a sleep study in Neuroendocrinology in 1997. Eight young adults in a 7-day crossover. Six older adults in a 14-day look. High-dose MK-677 at bedtime. In the young group, stage IV sleep rose about 50 percent and REM rose more than 20 percent versus placebo. Older adults showed a nearly 50 percent REM increase.

How sure? The numbers are striking. The sample is tiny. It is not a sleep-apnea drug trial. It is not a reason to skip the boring sleep work on how to sleep better. Dark room. Consistent bedtime. Daylight. Creatine and protein still exist. A secretagogue is not a mattress.

Hip-fracture files: IGF-I moved. The function bet did not cash.

Merck did not only study healthy older adults in a research ward. They tested whether raising IGF-I would help people get up after a hip fracture.

Bach and colleagues randomized 161 older hip-fracture patients to MK-0677 or placebo for six months. IGF-I rose 84 percent versus 17 percent on placebo. Functional performance did not show a statistically significant group win. The paper is honest about noisy function measures. It is also honest that GH stimulation may not buy the recovery people hoped for.

Adunsky and colleagues ran a later Phase IIb in 123 elderly hip-fracture patients at 25 mg a day. IGF-I rose. Most function measures did not. Gait speed had a signal. Stair-climbing power did not. The trial stopped early because of a congestive-heart-failure safety signal in a limited number of patients. The authors called the safety profile unfavorable in that population.

So what? A frail, post-fracture 70-year-old is not a 32-year-old in a group chat. Do not steal the IGF-I percentage and ignore the stop. Do not use a hip-fracture paper as a gym protocol. Heart failure is a clinician problem, not a comment-section debate.

Not a steroid. Not FDA-approved. Three access lanes.

Anabolic steroids are androgen-receptor chemistry. MK-677 is a ghrelin-receptor secretagogue. Different lock. Different banned-list conversation. WADA still cares about GH axis manipulation in sport. “Not a steroid” is not “legal for your tested league.”

Three lanes, same as the rest of this site:

• Labeled drug. Egrifta is tesamorelin for a specific indication. MK-677 does not have a U.S. retail muscle, sleep, or anti-aging sticker on this page.
• Compounded prescription. A clinician, a pharmacy, a script. Not a research catalog.
• Research catalog. A named chemical for laboratory use. It does not inherit a human indication because the bottle is pretty.

Chapman also studied oral MK-677 in selected GH-deficient adults who had used GH in childhood. That is a specialist file. It is not a license to self-diagnose adult GH deficiency from a forum poll. If a clinician is working up the axis, that is their job. This page maps the molecule. It does not treat the deficiency.

How to think about this without a black-market protocol

Here is the order I give beginners.

1. Name the lock. Ghrelin door or GHRH door. Oral or injectable. If you wanted tesamorelin’s visceral-fat literature, you are on the wrong page. If you wanted a two-door injectable pair, that is CJC no DAC plus ipamorelin.

2. Name the job. Curiosity about an oral GH secretagogue is a reading job. Treating sarcopenia, diabetes, sleep apnea, or “low GH vibes” is a clinician job. Those are not the same job.

3. Foundation first. Progressive training. Protein. Sleep. Then creatine. The creatine benefits page is grocery-aisle work with a deeper human file than most peptide captions. This page will never say skip creatine and swallow a secretagogue.

4. If an injectable even enters the chat, learn reconstitution math on how to reconstitute peptides — then stop. Protocol depth lives in Peptides & Pump Pro. Ten dollars a month. Seven-day trial.

This page is not for you if you want a blog to diagnose GH deficiency, treat diabetes, fix heart failure, or replace a clinician. Those visits still exist on purpose.

Where I actually look when the job is an MK-677 research compound

Education first. You already got the map. This block is the labs I will put my name on, with the codes that fire. Research-use catalog pages. Not a treatment claim. Not a “buy this to raise GH.”

Partner reality on today’s audit: Lee’s Drive Affiliate Link Generators sheet lists a Limitless oral MK-677 capsule SKU. That product page is a public HTTP 200. Limitless often login-gates professional pricing and emits out-of-stock schema until you are signed in, so I am not featuring a hero vial card off a gated shelf. BioLongevity, Peptira, Paramount, and S1 did not have an MK-677 product URL on that Drive sheet, so they get home or shop chips only. I will not invent a Paramount tablet href just because a shop page exists in the wild.

Research-catalog SKU currently live on the Drive sheet (not a treatment recommendation).

Limitless MK-677 capsules · LEE20Limitless home · LEE20BioLongevity home · LEE15Paramount home · LEE10Peptira home · LEES1 shop · LEE10

Limitless lists that capsule SKU as MK-777 / acetamoren on the storefront. Same Drive-sheet URL. Read the label. Match the product to the job. Do not collect bottles. Do not use a research catalog as a back door to a GH diagnosis.

Frequently asked questions about MK-677

Is MK-677 a peptide?

No. It is a small-molecule ghrelin-receptor agonist. Peptide shops sell it because buyers search it next to GH peptides. Format on the shelf is not format in the molecule.

Is MK-677 the same as ipamorelin?

Same door. Different key. Ipamorelin is an injectable peptide on GHS-R. MK-677 is an oral non-peptide on GHS-R. Read the ipamorelin map if the needle is what you actually typed.

Is MK-677 a steroid or HGH?

No. Steroids hit androgen receptors. HGH is the hormone itself. MK-677 asks the pituitary for a pulse. Those are three different conversations.

Is MK-677 FDA-approved for muscle, sleep, or anti-aging?

No. This page does not present MK-677, ibutamoren, or MK-0677 as an FDA-approved treatment for sarcopenia, GH deficiency in healthy gym adults, insomnia, obesity, or aging. Research-catalog capsules inherit neither an indication nor a manufacturing license for human use.

Will MK-677 make me hungry and mess with blood sugar?

The trial file says appetite can rise. Glucose and insulin sensitivity can move the wrong way. That is the ghrelin-plus-GH trade. Talk with a clinician if glucose is already a live issue for you.

Should I start with sermorelin instead?

Not as a default on this site. Sermorelin is the GHRH search term. The GH lane I actually map next to MK-677 is tesamorelin, CJC no DAC, and ipamorelin. Sermorelin still has a page. It is not the crown.

Can I just run an MK-677 protocol from a forum?

You can do a lot of unwise things. I would not. Name the molecule. Name the lock. Name whether you are holding a research catalog, a compounded script, or a fantasy about oral HGH. Protocol depth lives in Pro on purpose. This public page is the map, not the marching orders.

Selected references (research framing)

These are starting points for the published file — not a protocol, not a drug label, not an endorsement to self-treat. I am not inventing citations. Every ID below was verified against PubMed before publish.

• GHS receptor cloned in pituitary and hypothalamus, Science 1996 — PubMed 8688086
• Peptidomimetic regulation of GH secretion, Endocr Rev 1997 — PubMed 9331545
• Ghrelin identified as the endogenous GHS-R ligand, Nature 1999 — PubMed 10604470
• 7-day oral MK-677 in healthy young men, 24-hour GH profiles, JCEM 1996 — PubMed 8768828
• Daily oral MK-677 in healthy elderly, IGF-I restore plus glucose rise, JCEM 1996 — PubMed 8954023
• Oral MK-677 in selected GH-deficient adults, JCEM 1997 — PubMed 9329386
• Bedtime MK-677 and sleep stages, small crossover, Neuroendocrinology 1997 — PubMed 9349662
• MK-677 reverses diet-induced catabolism, short clinical file, JCEM 1998 — PubMed 9467534
• 2-year randomized trial in healthy older adults, fat-free mass vs function vs glucose, Ann Intern Med 2008 — PubMed 18981485
• Hip-fracture RCT, IGF-I up, function not significant, J Am Geriatr Soc 2004 — PubMed 15066065
• Hip-fracture Phase IIb stopped for a heart-failure signal, Arch Gerontol Geriatr 2011 — PubMed 21067829

Read primary sources. Do not treat a PubMed ID as a shopping list.

The bottom line

MK-677 is the oral ghrelin-receptor key. Ibutamoren. Not a peptide. Not a steroid. Not injectable ipamorelin in a capsule. Not tesamorelin. Not CJC no DAC. Same pituitary neighborhood as those injectables. Different lock-and-format story. Real randomized file in older adults. Real glucose and appetite caveats. Real hip-fracture programs that did not cash the function bet. No FDA muscle sticker on this page.

Keep the lanes. Read the papers. Do not skip a clinician because a capsule looked easier than a needle. Do not skip creatine because a secretagogue has a better nickname.

If you need the beginner on-ramp, use Start Here and what are peptides. Adjacent reading: ipamorelin, CJC-1295 and ipamorelin, tesamorelin, peptides for muscle growth, creatine benefits, and the Peptide Playbook.

I built Peptides & Pump so you can get this without a guru tax. If you want the protocol library, member discussions, and a place to think out loud before you spend money, that is Pro. If you are not ready to pay, use the free Knowledge Base first. Then come back and argue with me when you have read more than a caption.

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Supplier footnote: Drive-sheet MK-677 URL is the Limitless capsule page with ?couponcode=lee20. Limitless pricing is often login-gated, so that SKU is a chip, not a hero card. BioLongevity, Paramount, Peptira, and S1 had no MK-677 product URL on the Drive generators sheet at publish, so they stay home or shop chips. I will not invent those hrefs. Browse wider catalogs via BioLongevity home (code LEE15), Limitless home (code LEE20), Paramount home (code LEE10), Peptira home (code LEE), and S1 shop (code LEE10). Match the product to the job. Do not collect bottles. A research catalog is not a labeled GH drug.

Disclaimer. This article is for educational and research purposes only. It is not medical advice. It is not intended to diagnose, treat, cure, or prevent any disease. MK-677, MK-0677, ibutamoren, ibutamoren mesylate, LUM-201, acetamoren, ghrelin mimetics, GH secretagogues, and related research-catalog presentations are not presented here as treatments for growth-hormone deficiency, sarcopenia, frailty, hip fracture, heart failure, insomnia, obesity, diabetes, aging, or any other condition. A research-catalog product is not a compounded prescription and is not a labeled GH or anti-aging drug. Always consult a qualified healthcare provider before starting any peptide, drug, supplement, or protocol, especially if you have a medical condition or take prescription medication. Peptides & Pump does not sell peptides.

Affiliate disclosure. Some links on this page are affiliate links. If you buy through them, I may earn a commission at no extra cost to you. Codes LEE15, LEE20, LEE, and LEE10 are the ones I actually use where a coupon fires. That commission is how I keep publishing free education. I only link suppliers I am willing to put my name on.