Risk-free orders: 60-day money-back guarantee
Third-party tested · 99.635% pure
The oral growth hormone secretagogue, studied in 25+ human trials. Janoshik-verified 99.635% pure. 60 days in one bottle.
Rated 4.9 by 1,214 verified buyers
Why researchers pick it
Every number below comes from peer-reviewed human trials, not our marketing team. Full citations on the Science page.
Sleep
MK-677 amplifies the growth-hormone pulse the body naturally releases at night. In polysomnography research, participants recorded about 50% more stage-IV deep sleep and 20% more REM.
Recovery
A ~24-hour half-life keeps GH and IGF-1 elevated around the clock from one daily serving. In research, elevated IGF-1 is the primary driver of tissue repair, no injections, no reconstitution.
Growth signal
In published trials, MK-677 raised IGF-1 by 55% in two weeks and 88% by week four, and participants gained 3 kg of fat-free mass versus placebo in 8 weeks. It does not act on the testosterone feedback loop.
The problem with this market
An independent analysis published in JAMA bought SARMs products from the open internet and tested what was actually inside.
0%
of online SARMs products actually contained the labeled compound
0%
contained a different unapproved drug than advertised
0%
contained a substance in an amount different from the label
Van Wagoner RM, et al. Chemical composition and labeling of substances marketed as SARMs and sold via the internet. JAMA, 2017.
That's why every Primeletic batch is tested by Janoshik Analytical before a single bottle ships, and the certificate is public.
Third-party verified
Every batch goes to Janoshik Analytical, an independent lab, before a single bottle ships. Not a marketing claim: a public document you can hold us to.
0%
Identity: LC-MS
Mass spectrometry confirms the compound in the capsules is MK-677 (Ibutamoren), not something else wearing its label.
Purity: HPLC
Liquid chromatography measures how much of the sample is the pure compound. This batch assayed at 99.635%.
Match it yourself
The batch number on the certificate is printed on every bottle. Compare them. That's the whole point of publishing it.
Clinical data
MK-677 is one of the most-studied compounds in its class. These numbers come from peer-reviewed human trials.
+50%
Stage IV deep sleep
REM sleep +20% in the same trial. Recorded with polysomnography in healthy young adults.
Copinschi et al., Neuroendocrinology, 1997
+88%
IGF-1 at 4 weeks
+55% within the first 2 weeks at 25 mg daily. IGF-1 is the primary growth signal GH produces.
Chapman et al., JCEM, 1996
+3 kg
Fat-free mass in 8 weeks
Versus placebo, without a training program. Recorded by whole-body composition analysis.
Murphy et al., JCEM, 1998
2 yrs
Sustained elevation
GH and IGF-1 restored to young-adult range and held there. No desensitization observed.
Nass et al., Annals of Internal Medicine, 2008
Findings reported from published clinical research on MK-677; study populations and protocols vary. Full citations on the Science page.
How it works
No synthetic hormone enters the body, the compound amplifies the pulse the pituitary already fires.
Binds the ghrelin receptor
MK-677 is an oral ghrelin mimetic. It docks into the GHS-R1a receptor, the same switch the body uses to trigger growth hormone release.
The pituitary amplifies its GH pulses
The pituitary responds with stronger, natural GH pulses. No synthetic hormone enters the body: its own output is simply turned up.
IGF-1 climbs for 24 hours
The liver converts elevated GH into IGF-1, the primary growth and repair signal. A ~24-hour half-life means one serving covers the full day.
The natural axis stays intact
Signaling stays inside the body's own feedback loop. Research shows MK-677 does not act on the testosterone axis, so there is nothing to restore afterward.
The honest timeline
What the research and 1,200+ buyers report, week by week, including the parts other vendors leave out.
Side by side
Market figures from published prices of leading US vendors. We left their names out, their customers already know them.
| Primeletic | Typical liquid vendor | Typical capsule seller | |
|---|---|---|---|
| Format | Precision capsules, no droppers | Dropper bottle + math | Capsules |
| Supply per bottle | 60 days (120 caps) | ~25-30 days (50 ml) | 30 days (60 caps) |
| Cost per day | $0.58 | $1.60-$2.10 | $1.80-$2.60 |
| Public batch COA | Janoshik, linked on every page | Sometimes, buried in tabs | Rare or stale |
| Verified purity | 99.635% HPLC | Varies by batch | Usually unstated |
| On-page reviews | 1,214 verified | Off-site only | Usually zero |
| Money-back guarantee | 60 days, even empty bottles | 30 days, unopened only | None |
| Restocking fees | None | None | Up to 15% |
| Free US shipping | On 2+ bottles | Over $100 | Rarely |
Market figures reflect published prices of leading US vendors, February 2026.
Verified buyers
I bought this for recovery but the sleep is what sold me. By night four I was sleeping like I did at 19: heavy, full nights, waking up before the alarm. Recovery between leg days is noticeably faster.
I emailed asking about the lab report and they sent the Janoshik PDF for my exact batch number within the hour. 99.6% purity, tested this year. That's the whole reason I switched from my old liquid vendor.
Eating in a small surplus and lifting 5x a week. Up 4kg with the same waist measurement. Pumps are ridiculous and my elbows stopped clicking. Capsules beat measuring out liquid every night.
The timeline on their site is accurate: appetite is no joke the first two weeks, exactly like they say. Sleep and fullness are obvious by week three. Would be 5 stars if the 3-pack was always in stock.
Discreet packaging, batch number printed on the bottle matching the public COA, arrived in two days. This is how every vendor in this space should operate. Third order incoming.
I'm 41. Two decades of heavy pressing wrecked my shoulders. Six weeks in and I'm pressing pain-free for the first time in years. Skin and nails growing like weeds too. Something is clearly happening.
Risk, reversed
Run it for the full 8 weeks the clinical trials ran. If you're not satisfied, email us for a 100% refund, even if the bottle is empty. No forms. No return shipping. No restocking fees. No hard feelings.
Straight answers
No dodging. If your question isn't here, the full FAQ goes deeper, or email us and a human answers within 24 hours.
MK-677 is one of the most-studied compounds in its class. In a randomized trial, 25 mg daily raised IGF-1 55% within two weeks and 88% by week four. A 2-year study in Annals of Internal Medicine found GH and IGF-1 remained elevated with no desensitization. Every citation is on our Science page. We didn't write the numbers, the journals did.
Batch #1213681 · 312 bottles remaining
Tested, sealed, and shipped today. Covered for the full 60 days, even if the bottle comes back empty.
4.9 from 1,214 verified buyers · Free US shipping on 2+ bottles
