PepRank

MK-677

48%positive29 reports

Also: ibutamoren · Nutrobal

ExcludedSleepRecoveryOral

Oral GH secretagogue (not a peptide); hunger, bloat, insulin resistance, CHF signal.

not a peptide: ibutamoren, small-molecule ghrelin receptor agonist

#43 of 61 research peptides · updated
Access
Grey market
Cost / month
≈ €18–54
researchers' estimate; no listing to price
OralFelt in 15 min – 1 h, lasts 24 h
29 user reports
Glowing 3Positive 11Mixed 4Nothing 2Negative 6Bad reaction 3
  • r/NooTopics· · 47 upvotesOriginal ↗

    The mk has flipped my life on its head. I used to sleep 12+ hours, now I feel perfect off of 6.5, sleep study scores have tripled

    GlowingEnergy · 2.5 mg/day · Oral · ~3 months

    severe chronic fatigue for 5 years

  • r/suppgains· · 37 upvotesOriginal ↗

    MK677 solved a lot of long standing seemingly unrelated issues I had that no Dr had worked out, in the space of about a week.

    GlowingRecovery · Oral

    competitive bodybuilder also using AAS

  • r/moreplatesmoredates· · 62 upvotesOriginal ↗

    Second pic 🤬5 month ibutamoren. Feel like my arms shrunk lol? Might just be excessive water distorting the perception but not convinced. Can see overall way more water weight.

    NothingMetabolic · Oral · 5 months

Strict case
GH/IGF-1 elevation, insulin resistance and a CHF safety signal in an RCT.
Users report
Lifters like the appetite, sleep and fullness, but most say gains are mostly water and fat. People keep glucometers or berberine handy because of insulin resistance. Lethargy, tingling hands and bloat are routine. 'Just run HGH' is a common verdict.
Best effects
Appetite and weight gain · deeper sleep · fuller muscles (water) · IGF-1 increase
Downsides
Intense hunger · water retention / bloat · lethargy · numb/tingling hands
Watch
Raises fasting glucose and HbA1c; insulin resistance · Congestive heart failure signal: hip-fracture RCT terminated early (FDA category 2) · GH/IGF-1 elevation
Evidence
Human RCTs — Elderly, hip fracture, obesity; not approved
Typical use
10-25 mg/day oral. Users report 9.6–23 mg/day (median 20 mg, n=7).
Getting it
Never approved anywhere; sold as capsules or liquid by SARM and research-chemical shops, often mislabelled or swapped (MK-777 products have tested as LGD-4033). FDA category 2 bars compounding; banned by WADA.
Stacked with
RAD-140 or other SARMs: The classic SARM-shop cycle; makes it impossible to tell what MK-677 itself did, and one documented RAD-140 + MK-677 cycle ended with ALT at three times normal. · Berberine or metformin: Taken by many users to blunt the rise in blood sugar; some also keep a glucometer. · Testosterone or AAS cycles: Used alongside gear for sleep, appetite and recovery. · Enclomiphene: Paired in 'natty plus' cycles to keep testosterone up while on SARMs.

User reports 29

  • r/NooTopics· · 47 upvotesOriginal ↗

    The mk has flipped my life on its head. I used to sleep 12+ hours, now I feel perfect off of 6.5, sleep study scores have tripled

    GlowingEnergy · 2.5 mg/day · Oral · ~3 months

    severe chronic fatigue for 5 years

  • r/suppgains· · 37 upvotesOriginal ↗

    MK677 solved a lot of long standing seemingly unrelated issues I had that no Dr had worked out, in the space of about a week.

    GlowingRecovery · Oral

    competitive bodybuilder also using AAS

  • r/NooTopics· · 34 upvotesOriginal ↗

    felt like someone was massaging me the whole night, could sleep through a tornado, never slept deeper.

    GlowingSleep · Oral

  • r/workout· · 87 upvotesOriginal ↗

    My hands and feet would get super numb while working out. ... After the total 8 weeks I increased my bench from failing 215 to hitting 255. Gained around 15 lbs and had minimal side effects.

    PositiveRecovery · Oral · 8 weeks

  • r/moreplatesmoredates· · 32 upvotesOriginal ↗

    i took mk 677 for a month and went from 72-77kg. All my lifts went up (bench press +15kg). you get hungry but its not that bad, sleep and recovery were great but my left arm would feel numb at night.

    PositiveRecovery · Oral · 1 month

  • r/moreplatesmoredates· · 15 upvotesOriginal ↗

    it gives you insane hunger. I was dumb and couldn’t wait so I Ran a 2 week trial run and have been eating 4500-6000 calories a day 300+g protein and have gone broke form eating so much food

    PositiveMetabolic · Oral · 2 weeks

  • r/SARMsTalk· · 7 upvotesOriginal ↗

    I started taking MK-677 being very underweight and hardly eating at 107lbs... Off the top of my head the best progression I had over the 2 month span of taking MK-677 was Now I weigh 130LBS

    PositiveMetabolic · 10 mg/day, then 20 mg/day · Oral · ~2 months

    very underweight

  • r/DrWillPowers· · 5 upvotesOriginal ↗

    I experienced fairly intense growing pains following the first and second doses of mk. ... my bust has also grown like 2.5" in the time I've been taking it.

    PositiveOral · ~1 month, 5 days a week

    transgender woman using it for breast development

  • r/moreplatesmoredates· · 3 upvotesOriginal ↗

    I did 150 days of MK 25mg per day (in solution). I'm M, 26, 5'9" and started at 181. Natural other this. Ending weight was 196, and I've since cut back down to 185, maintaining steady there. So I think 3-4lbs of muscle is a good estimate.

    PositiveMetabolic · 25 mg/day · Oral · 150 days

    powerlifter, also changed diet and coach

  • r/SARMsTalk· · 2 upvotesOriginal ↗

    I've been on MK for 4 weeks. I have gained 5 kg and lost 1% fat… with a dose of 10mg, 2 days on and 1 day off.

    PositiveMetabolic · 10 mg, 2 days on 1 off · Oral · 4 weeks

  • r/workout· · 2 upvotesOriginal ↗

    Strength gains haven't been crazy but I definitely notice I am making more progress than I usually do in this time frame.

    PositiveRecovery · Oral · ~2 months

  • r/UARSnew· · 2 upvotesOriginal ↗

    I tried I thought it was placebo but it’s not sleep quality is crazy with this woke up like fresh

    PositiveSleep · Oral

    upper-airway resistance syndrome

  • r/moreplatesmoredates· · 2 upvotesOriginal ↗

    No height increase, I was always starving, horny, and energized. Best sleep of my life, honestly gains from mk677 are not worth doing it’s only worth it for it’s other effects

    PositiveSleep · Oral

  • r/SARMsTalk· · 1 upvotesOriginal ↗

    I just finished a 8 week run of mk-677 and the only negative side I had was the bloating which was very slight. My sleep was amazing super vivid dreams and recovery was for sure better.

    PositiveSleep · Oral · 8 weeks

  • r/SARMsTalk· · 13 upvotesOriginal ↗

    about a week in i developed pre diabetic symptoms from the food i was eating but i just kept pushing it. ... my takeaway is that mk does give you high bfp high water weight and it makes you get ugly.

    MixedMetabolic · ~30 mg/day · Oral · 1 month

  • r/workout· · 7 upvotesOriginal ↗

    For the whole 8 weeks my face was really puffy and I was bloated pretty much everywhere. ... Overall I wouldn’t recommend it to anyone still in puberty and honestly probably to anyone just because after you get off it has for me been very hard to gain strength.

    MixedRecovery · Oral · 8 weeks

    17 years old

  • r/moreplatesmoredates· · 3 upvotesOriginal ↗

    It's not bad, my lifts went up, much easier to bulk and saved my shitty appetite. However it increased my fasted blood sugar up to 95-105 range, I had to stop and within a week it went down to 74.

    MixedMetabolic · Oral

  • r/moreplatesmoredates· · 3 upvotesOriginal ↗

    The glucose issues are clear though. At least for me I could tell my blood sugar was messed up just by the way I felt. Taking berberine fixed the problems though.

    MixedMetabolic · Oral

    managed with berberine

  • r/moreplatesmoredates· · 62 upvotesOriginal ↗

    Second pic 🤬5 month ibutamoren. Feel like my arms shrunk lol? Might just be excessive water distorting the perception but not convinced. Can see overall way more water weight.

    NothingMetabolic · Oral · 5 months

  • r/SARMsTalk· · 1 upvotesOriginal ↗

    mostly cope bro i dosent rlly do much it just makes u bloated and fat

    NothingMetabolic · Oral

  • r/Testosterone· · 12 upvotesOriginal ↗

    My endo recently prescribed me Ibutamoren 12.5 ED PM. I've only been taking it for a week, but my weight has shot up. I've gained 8 lbs (170-178). I'm on a cut

    NegativeMetabolic · 12.5 mg/day · Oral · 1 week

    prescribed by an endocrinologist

  • r/moreplatesmoredates· · 5 upvotesOriginal ↗

    I used it when I didn’t know better. Helped with tennis elbow but the bloating and blood sugar was too much. In my opinion it ain’t worth it.

    NegativeRecovery · Oral

  • r/SARMsTalk· · 2 upvotesOriginal ↗

    i gained like 10kg off 8 weeks. did i get fat as fuck? yes. did i make a lot of gains? not really. its deadass just a pill that makes u eat more and sleep a little better.

    NegativeMetabolic · Oral · 8 weeks

  • r/UARSnew· · 2 upvotesOriginal ↗

    Ironically made my sdb worse probably because it swells your soft tissue and increases rem sleep which is usually the period of sleep that’s worst for UARS/OSA sufferers.

    NegativeSleep · Oral

    upper-airway resistance syndrome / sleep apnoea

  • r/NooTopics· · 2 upvotesOriginal ↗

    unless i took it as soon as i woke up the cortisol response from gh release was keeping me up all night

    NegativeSleep · Oral

  • r/workout· · 1 upvotesOriginal ↗

    Not worth it I don’t recommend I quit after 2 weeks, there are results but the side effects are worse than the positive effects

    NegativeMetabolic · Oral · 2 weeks

    15 years old

  • r/moreplatesmoredates· · 3 upvotesOriginal ↗

    20mg of MK absolutely rocked my blood sugar and blood pressure. Id be very careful with grandma.

    Bad reactionMetabolic · 20 mg/day · Oral

  • r/moreplatesmoredates· · 3 upvotesOriginal ↗

    I've been off ibutamoren for almost a week and I'm experiencing extreme fear and anxiety. Do you have any experience with this? Will it go away?

    Bad reactionMetabolic · Oral

  • r/workout· · 2 upvotesOriginal ↗

    I took it for a few months a few years ago. Increased my strength and energy but numb hands and I think it may have damaged the nerves in my hands long term

    Bad reactionRecovery · Oral · a few months

Safety

Tier by safety barStrict ExcludedBalanced ExcludedEvidence only Excluded

Seen harmMechanismData gapSilent harmProduct

Seen harm 2/3
A randomised trial in 123 older hip-fracture patients was stopped early for a congestive heart failure signal, which FDA cites as its reason for barring it from compounding. Adunsky et al. 2011: MK-677 in hip-fracture recovery, stopped for a heart-failure signal (PubMed 21067829) ↗FDA: bulk drug substances that may present significant safety risks (category 2 and withdrawn nominations) ↗
Mechanism 2/3
An oral ghrelin mimetic that raises IGF-1 by 50-70% for as long as it is taken; over two years it raised fasting glucose, cut insulin sensitivity and raised cortisol, with oedema. Nass et al. 2008: two-year MK-677 trial in older adults, glucose up and insulin sensitivity down (Ann Intern Med, PubMed 18981485) ↗Sevigny et al. 2008: MK-677 for 12 months in 563 Alzheimer patients (Neurology, PubMed 19015485) ↗
Data gap 1/3
Never approved, but tested in sizeable RCTs: 563 Alzheimer patients for a year and 65 older adults for two years. Sevigny et al. 2008: MK-677 for 12 months in 563 Alzheimer patients (Neurology, PubMed 19015485) ↗Nass et al. 2008: two-year MK-677 trial in older adults, glucose up and insulin sensitivity down (Ann Intern Med, PubMed 18981485) ↗
Silent harm 3/3
IGF-1-driven tumour promotion would be silent and delayed; the glucose rise shows on a blood test and fluid retention is visible. Nass et al. 2008: two-year MK-677 trial in older adults, glucose up and insulin sensitivity down (Ann Intern Med, PubMed 18981485) ↗
Product 2/3
Sold as grey-market oral research-chemical liquid or capsules.
Never if
Active cancer or a history of cancer · Heart failure or significant heart disease · Diabetes or impaired glucose tolerance · Pregnancy or breastfeeding (no human reproductive data)

Where to buy 0 in Europe · 5 total

ShopFormPricePer mgTesting
Nootropic SourceUSpowder · 10000 mg€270300 USD€0.027/mgOwn COA
Nootropic SourceUSpowder · 5000 mg€180200 USD€0.036/mgOwn COA
Nootropic SourceUSpowder · 1000 mg€4549.95 USD€0.045/mgOwn COA
Nootropic SourceUSsolution · 750 mg€6369.95 USD€0.084/mgOwn COA
SwissChemsUScapsules · 600 mg€6369.95 USD€0.10/mgThird-party tested

Studies 6

Sources 2

More in Hormones & libido all 12 →

  1. 1GHRP-6 Excluded Injection≈ €13–81 / month59%positive14 reportsFirst-generation GHRP used as an appetite drug for bulking; strong hunger, cortisol, glucose, GH axis.GH/IGF-1 axis elevation plus cortisol rise and reduced insulin sensitivity (FDA), with only single-dose human safety data.
  2. 2Kisspeptin YNWNSFGLRF (10 residues) Excluded Nasal / Injection≈ €4.1–12 / month52%positive30 reportsTop-of-axis GnRH stimulator for libido/testosterone; chronic use can crash the axis.Directly manipulates the HPG axis; continuous or long-acting exposure suppresses it.
  3. 3Hexarelin Excluded Injection≈ €27–110 / month45%positive5 reportsMost potent GHRP; fast desensitisation, acute cortisol/prolactin rise and direct CD36 heart effects.GH/IGF-1 axis elevation, acute cortisol and prolactin release, and GH-independent actions on heart and coronary vessels via CD36.
  4. 4IGF-1 DES Excluded Injection≈ €22–180 / month49%positive4 reportsShort-acting, truncated IGF-1 injected into the trained muscle; very potent at dropping blood sugar.An IGF-1 receptor agonist about ten times as potent as IGF-1 in cells and the most hypoglycaemic of the IGF-1 variants in primates, with no human data, the same tumour-promotion concern as LR3, and grey-market vials that are rarely tested.
  5. 5Follistatin-344 Excluded Injection≈ €180–450 / month44%positive10 reportsMyostatin/activin-binding protein sold as 1 mg vials; about half of tested vials held no follistatin.Blocks myostatin and activin signalling (FSH axis, angiogenesis, glucose) with no human safety data for the injected protein; vials often hold other drugs.
  6. 6IGF-1 LR3 Excluded Injection≈ €36–140 / month40%positive24 reportsLong-acting IGF-1 analogue (a cell-culture reagent) for muscle; hypoglycaemia, tumour-growth signal.A potent, long-acting IGF-1 receptor agonist with no human data at all: it accelerated tumour growth in mice, the same receptor causes hypoglycaemic seizures and carries a malignancy warning on the approved IGF-1 drug, and every vial is grey-market.
  7. 7Sermorelin YADAIFTNSYRKVLGQLSARKLLQDIMSR (29 residues) Excluded Sublingual / Injection≈ €38–94 / month46%positive29 reportsShort GHRH analogue; cheap, gentle, sleep-focused, still GH/IGF-1 axis.GH/IGF-1 axis elevation, though the mildest of the class.
  8. 8PT-141 DHFRWK (6 residues) Excluded Nasal / Injection≈ €24–170 / month39%positive30 reportsFDA-approved melanocortin libido drug; works strongly for many, raises blood pressure.Cardiovascular effects (BP spikes; contraindicated in CVD) and melanocortin pigmentation effects.
  9. 9GHRP-2 Excluded Injection / Nasal / IV≈ €18–45 / month39%positive7 reportsJapan-approved GH diagnostic sold as a vial; hunger, cortisol and prolactin spikes, GH axis.GH/IGF-1 axis elevation with cortisol and prolactin spikes; FDA notes raised insulin needs and deaths in critically ill subjects.
  10. 10Ipamorelin Excluded Injection≈ €11–100 / month42%positive51 reportsSelective ghrelin-receptor GH secretagogue; sleep and recovery, GH axis plus reactions.GH/IGF-1 axis elevation plus repeated anaphylaxis reports, including a coroner-attributed death.
  11. 11CJC-1295 YADAIFTQSYRKVLAQLSARKLLQDILSR (29 residues) Excluded Injection≈ €14–27 / month38%positive29 reportsLong-acting GHRH analogue stacked with ipamorelin; GH axis, vasodilatory reactions.GH/IGF-1 axis elevation plus FDA-noted tachycardia/vasodilatory reactions and anaphylaxis.

Sequence beads

Each bead is one amino acid in the peptide's chain, coloured by its side chain: grey for non-polar, cyan for polar, blue for positively charged and fuchsia for negatively charged. Length and mix tell related peptides apart at a glance, from a two-residue dipeptide like carnosine to a 43-residue protein like thymosin beta-4. The colours describe chemistry only and predict neither effect nor safety.

non-polarpolarpositivenegative

Report grades

Every first-hand Reddit or X report is graded on its own, from glowing through positive, mixed, nothing and negative to bad reaction, and the bar shows how those grades split. Posts that look vendor-adjacent stay on the peptide's page but are left out of the counts.

GlowingPositiveMixedNothingNegativeBad reaction

% positive

The share of a peptide's graded Reddit and X reports that are glowing or positive, vendor-adjacent posts left out. A peptide with few reports is pulled toward the average of all reports, as if it had eight average ones besides its own, so two glowing posts cannot top the list. Kept peptides rank by the same reports' mean grade, shrunk the same way, and excluded ones follow in that order.

Researcher estimate

No first-hand report of this peptide has been graded yet, so the figure is the researchers' own rating out of 10 from what they read about it. It ranks alongside the computed scores until reports arrive.

Safety tier

Each peptide is tiered clean, caution or excluded from its five risk axes under the chosen safety bar. An excluded peptide has a plausible route to serious harm, so it stays listed with the reason but ranks behind every other entry, however good its reviews.

Safety bar

The safety bar sets how much risk it takes to exclude a peptide. Strict: out on any serious mechanism with little human data, or any documented serious harm. Balanced: out on documented serious harm (unless it is obvious, reversible and from a regulated product), or a serious mechanism whose harm would be silent with no human data at all. Evidence only: out only on documented serious harm in humans that is lasting, delayed or from grey-market product.

Seen harm

Documented serious adverse events in humans, from 0 for none despite real exposure to 3 for deaths or several well-documented serious harms. Serious means a hospital or emergency visit or harm lasting weeks, so a headache or a bad night does not count.

Mechanism

A plausible biological route to serious harm at the doses people use, such as growth-factor signalling, hormone-axis suppression, heart or blood-pressure effects or immune activation. It runs from 0 when none is known to 3 when a dangerous pathway has been shown in living animals.

Data gap

How little human safety data exists for the molecule actually sold, from 0 for an approved drug with large trials and years of use to 3 for no human safety data at all. A modified analogue does not inherit its parent's trials.

Silent harm

Whether the feared harm would show quickly or stay hidden, from 0 when it is obvious and goes on stopping to 3 when it is silent and delayed, like tumour promotion or slow organ damage. User reports cannot reveal a harm that takes years to appear, so a high score here limits what good reviews can tell you.

Product

The risk of what people actually buy, from 0 for a regulated pharmacy or supplement product taken by mouth or on the skin to 3 for a grey-market injectable. In one dataset of 6,441 grey-market samples, 42–71% failed basic quality criteria and 15% carried endotoxin.

Evidence

The strongest kind of study behind the peptide's effects, from an approved drug through human controlled trials and small human studies to animal work or nothing of its own. Animal results often fail to carry over to people.

Access

How people get it: as an approved drug, a compounded prescription, an over-the-counter supplement or from the grey market, where nobody checks the vial. The channel decides both the legal position and the risk of a bad batch.

Price per month

Thirty days of the typical dose, from its low end to its high end, priced at the listing a careful buyer would choose: in stock, from a shop scoring 4 of 5 on trust (third-party tested where no score is set), failing that 3, a pure pack before a blend, a European shop first, then the cheapest per mg. The range is the dose's, not the shops'. A per-dose amount counts once a day unless the dose says otherwise. Prices are in euros at ECB rates of 2026-10-29, before shipping; the shop table keeps each listing's price per mg, per gram for bulk supplements. Where no listing can be priced the researchers' own estimate stands in, and says so.

Dose users report

The middle half of the daily doses stated in at least five first-hand reports, vendor posts left out. Where its middle sits more than twice above or below the declared dose, the month is priced at it as well, since what people take is what they pay for.

Testing

Whether the shop publishes lab results: third-party tested means an independent lab checks each batch, own COA means the shop's own certificate of analysis, and no public tests means neither. A certificate shows purity, not safety.

Added peptide

Some packs sold under one peptide's name hold a second one, such as 5 mg GHK-Cu in a nasal kit, stated only in the description. Sprayed in the nose or injected it reaches the blood like an injection, so it carries the risk of that route and is tiered as the injectable form, whatever its tier on the skin. A pack whose page gives no contents list may hold more than its name.