MK-677
Ghrelin Receptor Agonist | Growth Hormone Secretagogue
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What is MK-677?
MK-677 is a small molecule — not a peptide chain — that activates the same receptor as the natural hunger hormone ghrelin, which is why it's classified as a growth hormone secretagogue. Researchers study it for how it affects the body's own growth-hormone release, sleep patterns, and body composition, taken as a once-daily oral dose in study protocols. It's sold here strictly as a research chemical for laboratory study, not for human or animal use.
Key terms:
MK-677 is a small molecule ghrelin receptor agonist.
MK-677 (Ibutamoren) is a lab-made compound that switches on the ghrelin receptor, the target of the body's natural hunger hormone. Researchers study it for prompting growth hormone release without shutting down natural production. It works taken by mouth. Studies track effects on IGF-1 (a growth-related blood marker), sleep quality, and body composition through sustained growth hormone.
Key research areas
- 97% increase in 24-hour growth hormone secretion
- 40-72% IGF-1 elevation
- Sleep-quality changes reported in research
- Body-composition changes studied in research
- Sustained effects without suppressing natural GH production
Researched dosing
This table reflects how researchers structure MK-677 study designs — the oral dose ranges and timing used in published research, presented as study methodology, not personal usage instructions.
| Phase | Dose | Frequency | Route |
|---|---|---|---|
| Body-composition and longevity studies | 25mg | 1x daily | Oral (bedtime, empty stomach) |
| Sleep-quality studies | 25mg | 1x nightly | Oral (30 min before bed) |
| Starting dose | 12.5mg | 1x daily | Oral (assess tolerance first) |
| Standard study protocol | 25mg | 1x daily | Oral (clinical study standard) |
Commonly cycled 12 weeks on, 8+ weeks off.
How it works
At the cell level, MK-677 research looks at how the compound binds ghrelin receptors in the brain to trigger natural, pulsing growth-hormone release — the terms below just name that signaling pathway.
MK-677 mimics endogenous ghrelin by binding to GHS-R1a receptors in the hypothalamus and pituitary, triggering pulsatile growth hormone release while maintaining natural circadian patterns. Reported oral bioavailability of >60% eliminates injection requirements, with a 24-hour half-life enabling once-daily dosing in studied protocols.
Research applications
This section lists the research areas — tissue and metabolic research chief among them — that scientists have studied for MK-677; it summarizes what's been studied in the literature, not medical claims about people.
Tissue Repair
Reverses diet-induced catabolism with +2.69g/day nitrogen retention vs -8.97g/day placebo, supporting muscle preservation during caloric restriction. Increases fat-free mass by 1.1-2.7kg over 8-12 months with preferential lean tissue accrual and 15% basal metabolic rate increase within 2 weeks. 39-45% increase in bone formation markers including osteocalcin within 6-8 weeks, supporting bone turnover and potential fracture prevention.
Longevity
GH axis restoration supports longevity benefits including improved body composition, bone density, sleep quality, and metabolic function associated with age-related GH decline.
Energy Metabolism
15% basal metabolic rate increase within 2 weeks. Sustained growth hormone elevation improves fat metabolism and energy expenditure.
Dosage reference
- Doses used in research
- 25 mg
- Frequency in studies
- 1x daily
- Handling
- Reconstituted solution — research use only; not for administration
- Timeline reported in studies
- 2 weeks sleep quality, 12-16 weeks body composition changes
- Storage
- Room temperature, cool dry place
- Cycle length
- 8-12 weeks (research shows up to 18 months safety)
- Break between cycles
- Equal study-window duration (8-12 weeks minimum)
Interactions
This list shows which other compounds researchers study alongside MK-677, including growth-hormone-pathway peptides that show up often in the same study designs.
Reconstitution & storage
MK-677 is studied as an oral compound rather than an injectable, so this section covers handling and timing notes for research use rather than a mixing procedure.
- Use empty stomach (2+ hours after last meal)
- Maintain consistent daily timing
- Track sleep quality and appetite changes
- Store the reconstituted solution refrigerated (2–8°C), labeled with the date and concentration, for laboratory research use only.
Lyophilized: Room temperature, cool dry place, use within Per manufacturer expiration
Reconstituted: 2-6°C, use within Per manufacturer guidelines
Quality indicators
These are the documentation and sourcing checks researchers use to confirm an MK-677 sample is properly manufactured and tested before it goes into a study.
Pharmaceutical Grade Capsules - Professional capsules with clear labeling, batch numbers, expiration dates, and third-party testing certificates. Avoid research chemicals.
Proper Documentation - Certificate of analysis showing >98% purity, heavy metals testing, microbiological safety, and proper storage conditions during shipping.
Research Chemical Sources - Products labeled 'for research only' may have questionable quality control and are not intended for human consumption.
Dietary Supplement Claims - FDA prohibits MK-677 in dietary supplements. Any product claiming to be a legal supplement containing MK-677 is mislabeled.
Unknown Purity/Source - Products without certificates of analysis, proper labeling, or from questionable sources pose significant health and legal risks.
What to expect
This timeline summarizes what the research literature reports at each study stage — research context for comparing studies, not a personal-results promise.
Improved sleep quality, vivid dreams, possible appetite increase
Enhanced recovery, better sleep architecture, initial body composition changes
Noticeable lean mass gains, continued sleep benefits
Maximum body composition improvements, sustained GH elevation
Safety notes
This section covers MK-677's regulatory status and known research findings, including a terminated human trial — handling and regulatory context for researchers, not medical guidance.
- Contraindicated in heart disease, diabetes, active cancer, severe cardiovascular disease
- Decreases insulin sensitivity - monitor blood glucose closely
- May cause 5-15mg/dL fasting glucose elevation
- Requires baseline and ongoing monitoring: glucose, HbA1c, liver function, IGF-1
- FDA warns of 'significant safety risks due to potential for congestive heart failure'
- Not approved by FDA - investigational drug status only
Regulatory status
- Not approved by the FDA for any indication.
- Supplied and described for laboratory research use only — not for human or veterinary use.
Community data
Community Insights
Based on data the community reported. Not clinical proof.
Frequently asked questions
What is MK-677?
MK-677 (Ibutamoren) is a small molecule — not a peptide chain — classified as a selective ghrelin receptor agonist, which is why it is described as a growth hormone secretagogue. In the research literature it is studied for how it affects the body's own growth-hormone release and related markers. Lux BioPure supplies it strictly as a research chemical for laboratory study, not for use in people or animals.
What class of compound is MK-677?
MK-677 is a small-molecule ghrelin receptor agonist. Rather than a peptide, it is an orally active compound that binds GHS-R1a receptors in the hypothalamus and pituitary. Because it lacks an amino-acid chain, researchers confirm its identity through standard small-molecule chemistry testing instead of the sequence analysis used for peptides. It is sold for laboratory research use only.
How is MK-677 handled for research use?
MK-677 is studied as an orally active compound rather than an injectable, so it has no reconstitution or mixing procedure. In laboratory settings it is kept on a consistent handling schedule and, where a solution is prepared, refrigerated and labeled with its date and concentration. This reflects standard research handling, not a usage instruction for people.
How should MK-677 be stored in the lab?
Lyophilized MK-677 is generally kept at room temperature in a cool, dry place per its manufacturer expiration, while any reconstituted research solution is refrigerated at roughly 2–6°C. Researchers verify a sample against its Certificate of Analysis, looking for documentation of greater than 98% purity, heavy-metals testing, and correct labeling before it goes into a study.
Is MK-677 legal to purchase for research in Canada?
Lux BioPure sells MK-677 in Canada strictly as a research-use-only chemical for laboratory study — it is not for human or veterinary use and is not offered as a drug or supplement. MK-677 is not an approved drug; it holds investigational status only, and regulators have flagged safety findings from a terminated human trial as handling context for researchers.
References
Study was terminated due to increased heart failure incidence in elderly patients, establishing critical safety limitations and contraindications for cardiovascular disease.
View StudyMK-677 increased bone turnover markers including osteocalcin (39-45% increase), suggesting potential benefits for bone health through growth hormone axis activation.
View StudyMK-677 increased growth hormone secretion, fat-free mass, and energy expenditure in obese subjects while maintaining effects throughout treatment duration.
View Study