GH-axis
Oral secretagogue studies in defined clinical populations.1
HormonalSmall molecule
MK-677 / ibutamoren
Oral ghrelin-receptor agonist and growth-hormone secretagogue
Investigational ibutamoren; no FDA-approved product.
What does it do?
A nonpeptide GH secretagogue studied in older adults and other clinical populations. Higher GH and IGF-1 levels do not by themselves establish better function or longevity.
Body composition · recovery
Reported body-composition and recovery goals; appetite increases can conflict with weight-loss goals.415
Molecular information
4Amino-acid sequence
Not applicable: this compound is not a single peptide.
LengthNot a peptide sequence
Molecular weight · DaNot independently verified for the exact supplied form
Molecular formulaNot independently verified for the exact supplied form4
Salt, hydration, glycosylation and blend composition may change the supplied material; no unsupported formula or mass is assigned.
How long does it stay in the body?
Pharmacokinetics · How quickly the compound clears.
Half-lifeNo verified human estimate4
No numerical curve is shown without an exact compound, formulation and human-route match.
There is not enough numerical information in the checked sources to show a clearance curve.
What to expect
Study outcomes
Body-composition research is not longevity proof
The 65-participant study tested oral MK-677 in older adults. Changes in GH, IGF-1 or body mass cannot establish longer life or healthy performance benefits.1
Biomarker response did not improve Alzheimer outcomes
MK-677 increased IGF-1 but did not slow Alzheimer disease progression in a randomized trial.2
Reported timelines
Reference & communityWeeks 1–4; 4–12
Source sleep/appetite then composition reports; benefits not guaranteed.15
These are reported timelines, not a prediction of your response.
Doses by goal
Compare study doses and reported practices. Community and reference reports are unvalidated.
Scroll to compare all columns →
| Goal | Dose | Frequency | Route | Duration | Source |
|---|---|---|---|---|---|
| Older-adult body-composition studyHuman study65 adults aged 60–81 years | 25 mg | Once daily | Oral | Two-year modified-crossover design | 1 |
Population 65 adults aged 60–81 years Context Studied under protocol supervision; this is not a self-administration recommendation. | |||||
| Body composition/Anti-agingReference report | 25 mg | 1x daily | OralOral (bedtime, empty stomach) | 8-12 weeks (research shows up to 18 months safety) | 15 |
Population Population not independently verified; see the reference and linked research. Context Reported in Pep-Pedia’s educational protocol table. Study attribution and applicability to this exact product are not independently established. Source's glucose>100 mg/dL stop threshold is not a universal emergency threshold. Interaction categories do not establish safety. Source tabs Oral | |||||
| Sleep quality improvementReference report | 25 mg | 1x nightly | OralOral (30 min before bed) | 8-12 weeks (research shows up to 18 months safety) | 15 |
Population Population not independently verified; see the reference and linked research. Context Reported in Pep-Pedia’s educational protocol table. Study attribution and applicability to this exact product are not independently established. Source's glucose>100 mg/dL stop threshold is not a universal emergency threshold. Interaction categories do not establish safety. Source tabs Oral | |||||
| Conservative startReference report | 12.5 mgStarting dose | 1x daily | OralOral (assess tolerance first) | 8-12 weeks (research shows up to 18 months safety) | 15 |
Population Population not independently verified; see the reference and linked research. Context Reported in Pep-Pedia’s educational protocol table. Study attribution and applicability to this exact product are not independently established. Source's glucose>100 mg/dL stop threshold is not a universal emergency threshold. Interaction categories do not establish safety. Source tabs Oral | |||||
| Research protocolReference report | 25 mg | 1x daily | OralOral (clinical study standard) | 8-12 weeks (research shows up to 18 months safety) | 15 |
Population Population not independently verified; see the reference and linked research. Context Reported in Pep-Pedia’s educational protocol table. Study attribution and applicability to this exact product are not independently established. Source's glucose>100 mg/dL stop threshold is not a universal emergency threshold. Interaction categories do not establish safety. Source tabs Oral | |||||
No protocols match these filters.
Reported use periods and breaks. These do not establish a safe cycle or prove that breaks prevent tolerance.
Oral
- Use period
- 8-12 weeks (research shows up to 18 months safety)
- Break
- Equal cycle length (8-12 weeks minimum)
Reported timing
Bedtime (10:40 PM optimal) on empty stomach
Side effects & safety
Glucose effects
Fasting glucose increased in the short elderly-participant trial.
3Glucose and fluid retention
Insulin resistance, edema, appetite and lethargy; heart-failure concern.
Stop symptoms
Breathlessness/chest pain, marked edema, hyperglycemia symptoms, abnormal liver tests or severe fatigue.
Unapproved use
Heart disease, diabetes and malignancy require particular clinical review.
Not a complete safety screen. Discuss health decisions with a qualified clinician.
Combinations & interactions
9 entriesCheck cautions and reported pairings. A compatibility claim does not establish that a combination is safe.
HGH
Avoidance reportedOverlapping hormonal exposure.15
Reference report · Pep-Pedia label: Avoid CombinationInsulin
Caution reportedReduced sensitivity/glucose instability.15
Reference report · Pep-Pedia label: Use CautionLGD-4033
Caution reportedAdverse case report; causation/interaction uncertain.15
Reference report · Pep-Pedia label: Use CautionCJC-1295
Unverified pairingSource claim; excess GH concern.15
Reference report · Pep-Pedia label: SynergisticIpamorelin
Unverified pairingShared ghrelin receptor, not distinct mechanisms.15
Reference report · Pep-Pedia label: SynergisticGHRP-2
Unverified pairingOverlapping receptor stimulation.15
Reference report · Pep-Pedia label: SynergisticTB-500
Unverified pairingUntested recovery pairing.15
Reference report · Pep-Pedia label: CompatibleBPC-157
Unverified pairingUntested recovery pairing.15
Reference report · Pep-Pedia label: CompatibleOther medicines and research compounds
Not establishedNo clinical interaction study for the exact proposed combination was verified; absence of evidence does not establish compatibility.4
Research contextNo matching interactions. Try another name or filter.
Reconstitution
No universal bacteriostatic-water volume or validated preparation method is established for this entry.4
Reference preparation details
Reported handling information, not a validated formulation or instruction to prepare an injectable product.
Oral
The source describes capsules or measured oral material rather than vial reconstitution.
- Form
- Source describes a prepared product
- Reported parameters
- Storage follows the oral product instructions.
Appearance & documentation
Appearance and a purity certificate cannot establish sterility, identity, or suitability for injection.
Reported appearancePharmaceutical Grade CapsulesReported appearanceProper DocumentationReported variationResearch Chemical SourcesReported concernDietary Supplement ClaimsReported concernUnknown Purity/Source
15Available forms
No verified packaging examples included.
Packaging examples, not a market survey. Approved and research products are not interchangeable.
Storage after mixing
Reconstituted research vials
No applicable mixing data
The available sources describe prepared products or do not establish a reconstitution method.15
Storage depends on the formulation, diluent, container, and handling. Follow the specific product label or pharmacist’s instructions.
Evidence limits
View findings →Research-market product identity, purity and formulation cannot be established from a publication.1
Limited research. Some human research, but the checked evidence is small, early, narrow, inconsistent, or has important quality limitations. One trial does not establish broad benefit or safety.
Evidence definitions →Research findings
Human trialsSource context
Source's glucose>100 mg/dL stop threshold is not a universal emergency threshold. Interaction categories do not establish safety.
Compound identity & other names
A nonpeptide GH secretagogue studied in older adults and other clinical populations. Higher GH and IGF-1 levels do not by themselves establish better function or longevity.
Other names: MK-677
Investigational ibutamoren; no FDA-approved product.
Oral ghrelin-receptor agonist and growth-hormone secretagogue4
How it may work
Sustained GHS-R1a activation affects GH secretion, appetite and glucose physiology.15
Body-composition research is not longevity proof
The 65-participant study tested oral MK-677 in older adults. Changes in GH, IGF-1 or body mass cannot establish longer life or healthy performance benefits.
1Biomarker response did not improve Alzheimer outcomes
MK-677 increased IGF-1 but did not slow Alzheimer disease progression in a randomized trial.
2Research areas and evidence gaps
GH-axis research. Oral secretagogue studies in defined clinical populations.1
- Research-market product identity, purity and formulation cannot be established from a publication.
Additional uses listed by Pep-Pedia
Muscle/body composition and bone. Human lean-mass/nitrogen and bone-marker findings; fracture prevention unproven.15
Sleep and age-related hormone changes. Investigational sleep/GH outcomes, not established anti-aging treatment.15
Energy/recovery/appetite. Community goals; hunger can undermine weight-loss goals.15
Community reports Unvalidated
Body-composition discussions as described by Pep-Pedia.4
No representative survey, independently verified products, or controlled outcomes.
Search coverage and review status
No additional 2025–2026 peer-reviewed efficacy trial of this exact product was identified in this targeted check. Earlier evidence and unresolved listed references are retained.
- Checked
- 2026-10-12
- Search
- ibutamoren MK-677 2025 2026 trial site:pubmed.ncbi.nlm.nih.gov
- Catalog
- Pep-Pedia ↗ · 11 listed references retained
- Targeted search, not an exhaustive systematic review.
- Bibliography-only entries are retained for traceability and are not treated as verified findings.
AI-prepared summaries. Independent medical editorial review is pending.
Community poll 10 topics · Pep-Pedia snapshot
Voluntary, unverified reports. These percentages do not measure effectiveness or safety.
Experience
Number of responses to this question: not disclosed.
Duration of use
The source hides 1 additional categories. Their labels and percentages are unavailable.
Number of responses to this question: not disclosed.
Age range
The source hides 1 additional categories. Their labels and percentages are unavailable.
Number of responses to this question: not disclosed.
Gender
Number of responses to this question: not disclosed.
Primary goal
Number of responses to this question: not disclosed.
Effectiveness
The source hides 1 additional categories. Their labels and percentages are unavailable.
Number of responses to this question: not disclosed.
Side effects
The source hides 2 additional categories. Their labels and percentages are unavailable.
Number of responses to this question: not disclosed.
Dosage frequency
Number of responses to this question: not disclosed.
Would recommend
Number of responses to this question: not disclosed.
How discovered
Number of responses to this question: not disclosed.
Source & limitations
The source displays “250 responses” for this profile. This is not a confirmed participant count or a denominator for individual questions.
- Voluntary self-reports from Pep-Pedia visitors; identity, treatment, outcomes and timing are unverified. These data are not efficacy or safety estimates.
- The source displays a profile-wide response label, not a confirmed unique participant count. It stays unchanged across questions. Question-specific denominators and absolute option counts are not exposed.
- Only the top five categories are displayed for some questions. Extra categories are retained as an undisplayed-category count; their labels and percentages are unavailable.
- Displayed percentages are rounded. They may not total 100%, especially where categories are hidden.
- This is a dated snapshot, not a live survey or current recommendation.
References
Original sources and review status. Open a reference to read its summary.
1Effects of an oral ghrelin mimetic on body composition and clinical outcomes in healthy older adults: a randomized trialAbstract checked
AI-PREPARED SUMMARY
Two-year modified-crossover trial in 65 adults aged 60–81; body composition changes do not establish functional improvement or longevity.
Body-composition research is not longevity proof
The 65-participant study tested oral MK-677 in older adults. Changes in GH, IGF-1 or body mass cannot establish longer life or healthy performance benefits.
Pep-Pedia bibliography · Checked 2026-10-12
2MK-677: no clinical effect on Alzheimer disease progressionAbstract checked
AI-PREPARED SUMMARY
Randomized trial found no slowing of Alzheimer progression despite increased IGF-1.
Biomarker response did not improve Alzheimer outcomes
MK-677 increased IGF-1 but did not slow Alzheimer disease progression in a randomized trial.
Additional research · Checked 2026-10-12
3GH–IGF-1 axis stimulation with MK-677 in older adultsAbstract checked
AI-PREPARED SUMMARY
Short randomized study reported increased GH/IGF-1 and fasting glucose.
Additional research · Checked 2026-10-12
4Pep-Pedia: MK-677 / ibutamoren — community referenceCommunity source checked
AI-PREPARED SUMMARY
Accessed October 12, 2026. Secondary descriptions and bibliography; community schedules are unvalidated reports, not recommendations.
5Hip Fracture Recovery Trial - Terminated (2011)Pep-Pedia report · Primary source not checked
AI-PREPARED SUMMARY
Pep-Pedia reports: The hip-fracture study stopped early over a heart-failure signal in older patients, a clinically important safety limitation.
Reported population / model
Elderly patients
Reported study details
25mg oral daily · Study terminated early · Safety concerns - heart failure risk
Reported by Pep-Pedia; the linked publication, design, doses and result have not been independently verified here.
Read the Pep-Pedia report ↗Pep-Pedia reference card; original summary of its reported findings · Checked 2026-10-12
6Bone Turnover Markers Study (1999)Pep-Pedia report · Primary source not checked
AI-PREPARED SUMMARY
Pep-Pedia reports: Bone-turnover markers increased by a reported 39–45%; these surrogate changes do not prove lower fracture risk.
Reported population / model
Elderly adults
Reported study details
25mg oral daily · 2 months · 39-45% increase in bone formation markers
Reported by Pep-Pedia; the linked publication, design, doses and result have not been independently verified here.
Read the Pep-Pedia report ↗Pep-Pedia reference card; original summary of its reported findings · Checked 2026-10-12
7Body Composition in Obese Subjects (1998)Pep-Pedia report · Primary source not checked
AI-PREPARED SUMMARY
Pep-Pedia reports: The obesity study reportedly increased fat-free mass, GH and energy expenditure; improved body composition does not imply improved function or safety.
Reported population / model
Obese adults
Reported study details
25mg oral daily · 2 months · Increased fat-free mass and energy expenditure
Reported by Pep-Pedia; the linked publication, design, doses and result have not been independently verified here.
Read the Pep-Pedia report ↗Pep-Pedia reference card; original summary of its reported findings · Checked 2026-10-12
8Reversal of Diet-Induced Catabolism (1998)Pep-Pedia report · Primary source not checked
AI-PREPARED SUMMARY
Pep-Pedia reports: During caloric restriction, reported nitrogen balance was +2.69 versus −8.97 g/day with placebo; nitrogen retention is not a direct muscle-function outcome.
Reported population / model
Healthy adults
Reported study details
25mg oral daily · 7 days · +2.69g/day nitrogen retention vs -8.97g/day placebo
Reported by Pep-Pedia; the linked publication, design, doses and result have not been independently verified here.
Read the Pep-Pedia report ↗Pep-Pedia reference card; original summary of its reported findings · Checked 2026-10-12
9Sleep Quality Improvement Study (1997)Pep-Pedia report · Primary source not checked
AI-PREPARED SUMMARY
Pep-Pedia reports: Short-term sleep recordings reportedly showed more REM sleep in younger and older adults; durable sleep-disorder efficacy is unestablished.
Reported population / model
Young and elderly adults
Reported study details
25mg oral daily · 1 week · 20% REM increase in young, 50% in elderly
Reported by Pep-Pedia; the linked publication, design, doses and result have not been independently verified here.
Read the Pep-Pedia report ↗Pep-Pedia reference card; original summary of its reported findings · Checked 2026-10-12
10Growth Hormone Stimulation in Elderly (1996)Pep-Pedia report · Primary source not checked
AI-PREPARED SUMMARY
Pep-Pedia reports: The source reports 97% higher daily GH secretion in older adults; a hormone increase alone is not evidence of improved health.
Reported population / model
Elderly adults
Reported study details
25mg oral daily · 2 weeks · 97% increase in 24-hour GH secretion
Reported by Pep-Pedia; the linked publication, design, doses and result have not been independently verified here.
Read the Pep-Pedia report ↗Pep-Pedia reference card; original summary of its reported findings · Checked 2026-10-12
11LGD-4033 and MK-677 use impacts body composition, circulating biomarkers, and skeletal muscle androgenic hormone and receptor content: A case reportLinked reference · Not independently reviewed
REFERENCE NOTE
Listed in Pep-Pedia’s bibliography; the linked publication and its findings have not been independently verified in this pass.
Pep-Pedia bibliography · Checked 2026-10-12
12Structural basis of human ghrelin receptor signaling by ghrelin and the synthetic agonist ibutamorenLinked reference · Not independently reviewed
REFERENCE NOTE
Listed in Pep-Pedia’s bibliography; the linked publication and its findings have not been independently verified in this pass.
Pep-Pedia bibliography · Checked 2026-10-12
13A Study of the Metabolism of Ibutamoren (MK-677), a Growth Hormone Secretagogue, in Human Urine by Ultra-High-Performance Liquid Chromatography–High-Resolution Mass SpectrometryLinked reference · Not independently reviewed
REFERENCE NOTE
Listed in Pep-Pedia’s bibliography; the linked publication and its findings have not been independently verified in this pass.
Pep-Pedia bibliography · Checked 2026-10-12
14Effect of the Orally Active Growth Hormone Secretagogue MK-677 on Somatic Growth in RatsLinked reference · Not independently reviewed
REFERENCE NOTE
Listed in Pep-Pedia’s bibliography; the linked publication and its findings have not been independently verified in this pass.
Pep-Pedia bibliography · Checked 2026-10-12
15Pep-Pedia: MK-677 / ibutamoren — route-specific referenceReference page checked; underlying claims require separate verification.Community source checked
AI-PREPARED SUMMARY
Source page checked across available routes. Protocols, cycles, storage, mechanisms and pairing claims are secondary reports; checking the page does not independently validate those claims. Original concise summaries are used here.
Content coverage audit · Checked 2026-10-12