MK-677, also called ibutamoren, is one of the most studied compounds we sell. It isn’t a SARM and it isn’t a peptide. It’s an oral growth hormone secretagogue that Merck developed in the 1990s, and it has more human trial data behind it than most compounds in this category.
In this guide
What is MK-677?
Ibutamoren mimics ghrelin, the hunger hormone, and binds the GHS-R1a receptor in the pituitary. That tells the pituitary to release growth hormone, which in turn raises IGF-1. Because it works through the ghrelin receptor, it doesn’t act on the androgen receptor at all.
It’s active when taken orally and has a half-life of about 24 hours, which is why Merck studied it as a once-daily compound.
MK-677 research findings
The best-known study is a two-year trial in healthy adults aged 60 to 81. A daily dose of 25 mg raised IGF-1 into the range typical of young adults and increased fat-free mass compared with placebo. A 1998 study in young men on a calorie-restricted diet found it reversed the protein loss that normally comes with dieting.
Other studies looked at bone turnover, sleep quality and recovery after hip fracture. You can search the full list on PubMed.
MK-677 side effects reported in trials
The trials reported increased appetite, mild fluid retention and higher fasting blood sugar, along with reduced insulin sensitivity in some participants. Merck never brought it to market, and it isn’t approved by the FDA for any use.
MK-677 compared with peptides like ipamorelin
Peptide secretagogues such as ipamorelin and GHRP-6 act on the same ghrelin receptor but break down quickly. Ibutamoren’s oral activity and long half-life are what set it apart in research.
Where to buy MK-677
Sports Technology Labs sells ibutamoren in two formats. Liquid MK-677 comes at 25 mg/mL in a 30 mL glass dropper bottle, made with USP-grade PEG-400. MK-677 powder comes in a 2 gram pouch for labs that prepare their own solutions. The current batch tested at 99.97% purity with MZ Biolabs.
It’s also part of several stacks, including the MK-677 and Ostarine stack, the RAD-140 and MK-677 stack and the LGD-4033 and MK-677 stack, which cost less than buying the bottles separately.
Storing liquid and powder ibutamoren
Liquids from Sports Technology Labs are dissolved in USP-grade PEG-400 and bottled in UV-resistant glass with a glass dropper fixed into the cap. Keep the bottle upright, tightly capped and out of direct sunlight. Room temperature is fine, and there’s no need to refrigerate. If a bottle gets cold in transit and looks cloudy, let it warm to room temperature and swirl it gently.
Powder ships in a resealable foil pouch. Measuring tools aren’t included, so you’ll need an analytical balance that reads to at least 1 mg. Most labs dissolve it in PEG-400, the same carrier we use for our liquids. Reseal the pouch straight after use and store it somewhere cool, dry and dark.
How to read the COA
Each product page lists the purity and the COA date. Purity is the share of the target compound found by HPLC. The date tells you when that batch was tested. Most listings also show the certificate and the chromatogram in the image gallery, and we’ll email the full document if you ask. A single tall peak at the expected retention time is what you want to see. Small extra peaks are impurities, and the purity figure accounts for them.
MK-677 FAQ
Is MK-677 a SARM?
No. It’s a growth hormone secretagogue. It’s often sold alongside SARMs because researchers study them together.
How long is ibutamoren’s half-life?
About 24 hours.
Does MK-677 affect testosterone?
It doesn’t bind the androgen receptor, so it isn’t expected to suppress testosterone directly.
Ready to order? Buy MK-677 from Sports Technology Labs with free US shipping on orders over $149.
Everything sold by Sports Technology Labs is for laboratory research only. It isn’t for human or veterinary use, isn’t a dietary supplement and hasn’t been approved by the FDA. Nothing in this article is medical advice.