THIS PRODUCT IS INTENDED AS A RESEARCH CHEMICAL ONLY. This designation allows the use of research chemicals strictly for in vitro testing and laboratory experimentation only. All product information available on this website is for educational purposes only. Bodily introduction of any kind into humans or animals is strictly forbidden by law. This product should on be handled by licensed, qualified professionals.

SKU: MK-677 Category:


Concentration 30 mg per mL
Size 900 mg / 30 mL
Stability Room Temperature
Physical Appearance Clear Liquid
Molecular Formula C28H40N4O8S2
LC-MS & HPLC 99% Purity

About MK-677

The MK-667 compound is a selective antagonist of the ghrelin receptor and is very orally active. Research studies on the compound have shown that MK-667 peptide increases the secretion of insulin-like growth factor 1 (IGF-1) and growth hormone (GH) without affecting cortisol levels. There are ongoing research and clinical studies to determine if the compound can be used as a viable treatment option for bone wasting, growth hormone deficiency, and muscle wasting. Other areas of interest include appetite enhancement and the treatment of Alzheimer’s disease. Ready to discover more about MK-667 and its possible effects on overall health.

What is MK-677?

MK-667 is also referred to as Ibutamoren and Oratrope and is an antagonist of the ghrelin receptor. Besides being a very potent research chemical, Ibutamoren is an orally active compound. Therefore it’s a mimetic of the ghrelin and growth hormone secretagogue. MK-667 isn’t a peptide or a ghrelin analogue and shares zéro structural similarities with ghrelin. Scientific evidence shows that the compound triggers the section of the insulin-like growth factor 1 (IGF-1) and growth hormone (GH). But it doesn’t interfere with cortisol levels. Therefore it can trigger the growth of lean muscle mass. Ongoing scientific studies focus on using the compound an s possible treatment option for bone wasting, growth hormone deficiency, appetite stimulation, and muscle wasting. The MK-667 is highly valued because of its excellent oral bioavailability and long half-life. A human study showed that the compound elevated levels of IGF-1 for up to 24 hours with a single dosage of MK-667.

MK-677 and SARMs

Most of the time, Ibutamoren is grouped under the category of selective androgen receptor modulators (SARMs) since it doesn’t fall in the peptide or ghrelin categories. However, MK-667 isn’t a SARM compound. Instead, it’s a complex, synthetic chemical propanamide derivative that functions as a ghrelin receptor agonist. Even though it’s not a peptide, due to its effects, Ibutamoren falls in the growth hormone secretagogue peptides category. It boosts GH release and binds to the ghrelin and growth hormone secretagogue receptors while maintaining the normal pulsatile and physiologic patterns of GH fluctuations. The same effects are observed in GHRP-2, GHRP-6, Ipamorelin, and hexarelin.

The key benefit of MK-667 is that it’s not a SARM compound because selective androgen receptor modulators can decrease testosterone levels by negatively impacting natural androgen production. Administration of SARMs must be highly controlled, and their cycle should be on and off to mitigate their effect on natural androgen production. Such precautions aren’t required when using MK-667.

MK-677 Chemical Structure

  • Molecular Formula: C27H36N4O5S
  • Molecular Weight: 528.7 g/mol
  • Synonyms: MK-0677, Oratrope, Ibutamoren, L-163,191

MK-677 Research and Effects


Scientific studies and evidence confirm that muscle mass and growth hormone secretion decline start after mid-puberty. The ultimate result is the loss of muscle visible in older adults. The progressive decline in the production of insulin-like growth factor 1 (IGF-1) and growth hormone (GH) is called somatopause. Findings from the study showed that a 70-year-old male could produce 60% of the GH that he produced when he was 18 years old. A decrease in the secretion of the IGF-1 and GH can cause body composition changes and bone density loss, among many other age-related side effects. Surprisingly the IGF-1 and GH levels are boosted by estrogen and progesterone, reducing somatopause’s effects in women as they get older.

MK-667 and other similar compounds can slow the effects of somatopause and even halt the process. Hence causing improved bone strength and growth of lean muscle mass among the elderly, thus improving several body functionalities. Even though the research studies investigating this possibility are still in the early stages, the results are encouraging.

Improving Body Composition

MK-667 is known for effectively enhancing the production of the IGF-1 and GH hormones. Simultaneously boosting the two hormones can enhance nitrogen retention, essential in a parenteral nutrition setting. A single dosage of Ibutamoren can trigger the above effects, making the compound a potential staple for patients in ICU. Research studies have confirmed that Ibutamoren can trigger GH/IGF-1 increase to levels similar to those observed in healthy young adults without causing adverse side effects. Instead, the subjects experienced zero change in the HDL cholesterol, increased lean muscle mass, and decreased LDL cholesterol. Ibutamoren is a potential long-term viable treatment for body decomposition and muscle wasting effects caused by aging.

Administration of MK-667 seems to have limited effects on body composition. Scientists suspect combining the compound with a healthy diet and frequent workouts will substantially help increase muscle strength, growth of lean muscle mass, and boost bone density. 

Bone Density

According to a study on young, obese males, Ibutamoren altered bone function significantly. The compound increased bone resorption and deposition, with the same results observed in elderly test subjects. The findings confirm that increased bone remodeling can negatively or positively affect settings. When the increased bone remodeling is combined with exercise, it can cause improved bone strength and enhanced resistance to fracture.

During a research study on elderly individuals with hip fractures by a multi-center study, administration of MK-667 caused improved gait speed and lesser numbers of falls. Confirming the fact that Ibutamoren indeed enhances bone density and bone function. In another study that involved a nine weeks trial on MK-667, subjects reported an increase in serum osteocalcin (30%) and bone-specific alkaline phosphatase (10%). The two markers confirm an increase in bone density. Individuals in the study showed more independent living after suffering a hip fracture.

Neurological Function

Past animal studies confirm that IGF-1 is critical in eliminating the amyloid beta from the body’s central nervous system. One of the side effects of having too much amyloid beta is the onset of Alzheimer’s disease (AD). AD is more frequent in older people who suffer from low levels of IGF-1. Counteracting the effects of amyloid beta accumulation could be triggered by raising the levels of IGF-1, thus acting as a preventative option for AD.

A study on older adults diagnosed with AD showed that MK-677 increased the IGF-1 levels substantially and, however, didn’t alter the progression of the disease after diagnosis. Researchers are investigating where the compound can be used to prevent and treat AD. However, the research is limited due to time and the high cost. So far, research studies on mice confirmed that Ibutamoren appeared to prevent AD as long as the compound was administered before the substantial accumulation of the amyloid beta.

Improve Sleep

Ibutamoren is more potent in improving sleep compared to GHRPs. According to a research study, MK-667 increased sleep duration in stage 4 by 50% and REM sleep by 20%. The results were profound when administered to older adults, with REM sleep increasing by 50% and a substantial decrease in REM latency. Stage four sleep is considered the most critical stage in sleep, as it facilitates the most severe wound healing and tissue repair and preserves the brain’s waking function. In children, stage four helps in facilitating growth. Researchers believe prolonging this stage of sleep can cause enhanced muscle recovery, brain development, and function. MK_667 can be a viable product in prolonging stage four sleep.

Heart Health

Endothelial progenitor cells are stem cells that play a crucial role in blood vessel regeneration. A decrease in the endothelial progenitor cells can lead to atherosclerosis; a hitch can cause cardiovascular health problems like heart attacks and high blood pressure. Studies on mice showed that increasing the GH levels helped substantially reduce the decrease of endothelial progenitor cells caused by aging. Hence reducing cardiovascular-related health complications. As we age, the nitric oxide levels reduce, and nitric oxide plays a crucial role in regulating the blood vessel’s health and maintaining normal blood pressure levels. Scientific studies show that GH treatment increased NO synthase expression and levels in mice, effectively regulating blood pressure and reducing the risk of cardiac diseases, stroke, and kidney disease.

Research studies on Ibutamoren show that the compound can trigger the enhanced secretion of GH and IGF-1 in humans and animals. The compound doesn’t fall in the category of a peptide or a SARM, making it have unique qualities absent in the two categories. MK-667 has undergone several human trials and is considered a safe compound and free of side effects, even though it hasn’t been approved for human use yet. While scientists continue researching more benefits associated with the compound, we must recognize the fantastic health benefits of MK-667, such as improving appetite, body composition, cardiac health, muscle strength, and neurologic function. It also has excellent potential to enhance overall cardiovascular health and be an alternative preventive option for atherosclerosis and Alzheimer’s disease.

Ibutamoren is one of the most potent compounds in the health and pharmaceutical industry, with great potential in cardiovascular health. More research is expected to shed more light on the possibility of using the compound to treat various prevalent diseases.

Additional information

Weight 0.15625 kg