MK-677 and Erectile Dysfunction

Dr. Mike Jansen

Last Updated December 17, 2022

Dr. Mike Jansen

 December 17, 2022

Curious about MK-677 and erectile dysfunction?

Do you want to know if MK-677 can help men suffering from performance issues, and other health-related problems?

Then you’ve come to the right place. In this comprehensive guide, we take an in-depth look at MK-677 and whether or not it helps men suffering from erectile dysfunction.

We also answer your most important questions, including:

  • Is MK-677 a steroid?
  • What are the benefits of MK-677?
  • Can MK-677 be “stacked” with other supplements?

…And much more!

Our team has looked through several studies and proven data which offer in-depth, clinically-based answers to these questions and more, so that you are able to access the most current and accurate information available.

By the end of this guide, you’ll have all the facts available so you can make an informed decision about whether MK-677 is right for you.

Disclaimer: The contents of are for informational and educational purposes. We do not provide legal advice. Likewise, we do not provide medical advice, diagnosis, or treatment. Please consult your physician prior to consuming any over-the-counter supplements, like a natural testosterone booster, and/or getting a prescription for a pharmaceutical medication. Your access to is subject to our full disclaimer and terms of use.

MK-677 and Erectile Dysfunction

One of the most concerning issues men have when considering whether or not to take MK-677 is if MK-677 can cause erectile dysfunction.

Let us put your fears to rest here – not only does MK-677 not cause erectile dysfunction, but it can even be beneficial for your libido and the quality of your erections.

Before we jump into how MK-677 can help improve your libido, we need to address the origin of why men are concerned that taking this growth hormone secretagogue can cause erectile dysfunction.

Mainly, this is due to data showing an increase in prolactin production while cycling MK-677.
However, this elevated level of prolactin only tends to become an issue when the recommended dosage of MK-677 is also exceeded, which is often anything above 25mg/ml [1].

MK-677 And Prolactin

How does prolactin affect libido, you might ask?

Without diving into a lengthy explanation, prolactin is a hormone mainly responsible for lactation (production of breast milk) and breast tissue development. Prolactin levels are normally low in males, and high in women who are pregnant.

If too much prolactin is circulating in the bloodstream, this is called hyperprolactinaemia. Symptoms can include the unwanted production of milk, and most importantly, testosterone deficiency.

As a result of weakened testosterone production, conditions like erectile dysfunction can arise [2].

In a case like this, the quick fix would be to simply lower the dosage of MK-677, or stop taking it altogether.

MK-677 And Libido

In terms of how MK-677 can help improve your libido, the science is pretty clear: clinical evidence suggests that growth hormone deficiency is linked to low libido and erectile dysfunction.

With that said, raising GH levels by taking MK-677 may help boost sexual power. [3, 4]

In addition, studies have also shown that IGF-1 deficiency can cause low libido and erectile dysfunction.

MK-677 can be beneficial in this regard as well, since it increases IGF-1 levels in the body. These benefits are not only limited to younger males, but also to older men, where those who took MK-677 reported improved levels of general well-being and libido [5, 6].

What is MK-677?

Since it was first synthesized in 1985, growth hormone (GH) has been applied in several cases to provide solutions for individuals suffering from a number of ailments, such as GH deficiency and osteoporosis [7].

However, GH usage has plenty of drawbacks, not to mention that it can be an expensive and uncomfortable method of treatment, since exogenous GH must be injected into the body.

As a result, researchers began developing a more accessible alternative. In 1995, MK-677 was finally synthesized and produced by the Pharmaceutical Company “Reverse Pharmacology” under the trade name “Nutrobol”. Other names for MK-677 include ibutamoren and MK-0677 [8].

Legal Growth Hormone

MK-677 is often marketed as ‘legal growth hormone’, although this can be a bit misleading.

Whereas GH is directly injected into the bloodstream, MK-677 has a different mechanism of action, since it’s actually a growth hormone secretagogue and ghrelin receptor agonist.

This simply means that MK-677 signals the pituitary gland to increase the endogenous secretion of GH and IGF-1, as opposed to synthetic GH, which is injected directly into the bloodstream. Just for reference, the pituitary gland is a small, pea-sized gland located at the base of your brain below your hypothalamus.

It’s a part of your hormonal system, and is responsible for releasing a number of different hormones into your system, including GH.

MK-677 Benefits

There are a number of reasons for why bodybuilders and athletes are starting to prefer MK-677 over GH. Firstly, GH can be costly to run over an extended period of time.

Also, it’s much more convenient to ingest MK-677 orally, rather than having to take routine injections. Additionally, MK-677 doesn’t require any special sort of storage, whereas GH must be maintained at low temperatures.

Ingesting MK-677 causes GH to be secreted by the somatotrophes of the anterior pituitary gland through several pulses on a daily basis, rather than one large burst as is the case with injecting GH.

Growth hormone then enters the bloodstream, causing the liver to produce insulin-like growth factor-1 (IGF-1), another crucial hormone in our bodies which facilitates several metabolic effects.

To be clear, MK-677 does not cause more GH pulses to happen.

Instead, it stimulates a greater total 24 hour GH production rate [9]. In other words, ingesting MK-677 can strengthen and augment each GH pulsation that occurs in the body.

In addition to being a potent growth hormone secretagogue, MK-677 is also an oral ghrelin mimetic.

Ghrelin is a hormone excreted by the stomach in order to regulate your appetite. This is another reason why MK-677 has become so popular with bodybuilders, as it can ramp up your appetite and thus increase your caloric intake [9].


How to Take MK-677 | What You MUST Know

The most serious bodybuilders and strength athletes are usually willing to consume a number of potentially dangerous substances in order to secure greater results in the gym, such as using hypodermic needles to administer anabolic compounds and GH.

On the other hand, natural athletes may prefer to seek alternative and less risky means of boosting their performance.

Fortunately, when it comes to taking MK-677, the use of a hypodermic needle isn’t required.

As of right now, in early 2023, MK-677 is only commercially available in the form of capsules and liquid. This means it can be conveniently taken along with a meal, or even mixed into a beverage.

According to the dosing guidelines set out above, we wouldn’t recommend exceeding more than two cycles of MK-677 per year.

While you’ll still feel its benefits, you can be sure to avoid any possible side effects by being cautious with the amount taken. Typically, the optimal daily dose of MK-677 lies between 10 and 25mg/ml. It can be taken once per day, or split up into two doses – one in the morning, and one in the evening [10].

Best MK-677 Supplement | 2022 Edition

Several vendors on the internet are selling various bodybuilding and health supplements like MK-677.

Our team has launched a full-fledged investigation into which of these sources have the best MK-677 supplements available. These sources have been evaluated according to strict criteria:

  • Are the products reasonably priced?
  • Do the products have a high purity?
  • Do they offer fast shipping available worldwide?

And finally, do they already have a number of satisfied customers who have posted positive reviews of their experience using MK-677?

After a thorough investigation, our team identified a legitimate and reputable vendor to buy MK-677 from: Chemyo. Here’s why:

  • Positive reviews. At the time this article was written, in early 2023, Chemyo MK-677 already has amassed over 45 positive reviews from verified customers – a strong indication that their supplement is indeed effective.
  • Fast shipping. They also offer free shipping on domestic orders over $100, and free international shipping on orders exceeding $275. However, Chemyo may not provide shipping to your country, so be sure to double check before placing your order.
  • Certified lab reports. You can view a number of up-to-date lab reports certifying the purity of Chemyo’s products, such as Chemyo MK-677. They provide full documentation for each product and batch, including IR, GC-MS, LC-MS and HLPC, as opposed to other companies that only provide a certificate of authenticity.
  • High-quality products. Chemyo’s products are all produced in accordance with high standards of quality in an FDA-approved facility in the United States.

We strongly suggest purchasing two bottles of Chemyo MK-677, so that you’ll have enough to run a proper 3 month cycle.

You can visit them here to learn more and purchase Chemyo MK-677:

Order MK-677 from our top-rated USA vendor...

MK-677 Benefits

You might be wondering – what are the benefits of MK-677?

While there are many advantages to consuming this growth hormone secretagogue, it’s important that we first take a look at the benefits to be derived solely from the increased release of GH and IGF-1.

Improved Body Composition

Healthy GH and IGF-1 levels are essential to the body developing properly.

In fact, the anti-aging properties of GH are particularly important, so much so that GH is often referred to as the “fountain of youth”. This is because the natural secretion of GH tends to diminish over time, which also causes serum IGF-1 levels in the body to drop.

The result is pronounced lean muscle catabolism and increased mortality [9].

This may explain why so many celebrities and famous figures tend to subscribe to GH therapy later on in life.

The benefits of GH and IGF-1 are numerous when taken in reasonable quantities. GH promotes and increases protein synthesis, which allows more muscle to be built.

Higher GH levels also lead to higher levels of fat metabolization, which lowers bodyfat levels. It can also produce an improvement in one’s complexion by tightening up loose skin, accelerate hair growth, improve sleeping patterns, and increase bone density, which can prevent fractures [11].

One of the most eye-catching benefits about higher IGF-1 levels in terms of bodybuilding, is that it supports cellular division (hyperplasia).

This is extremely unique in that IGF-1 is the only hormone with the ability to induce brand new muscle cell growth via muscular cell division.

MK-677 Specific Beneifts

As far as benefits gained specifically from MK-677, numerous studies have uncovered the following:

MK-677 can increase nitrogen retention even when the body is experiencing a calorie deficit, due to its anti-catabolic properties.

MK-677 can also reverse nitrogen wasting, which provides help for not only bodybuilders that want to maintain their muscle on a cut, but also for those suffering from chronic disease and muscle wasting [12].

An improvement in sleep quality is also a notable benefit of MK-677.

We can refer to a study with eight participants between 18 and 30, as well as six elderly subjects concluded that MK-677 consumption could boost REM sleep by as much as 50% [13].

Another powerful benefit from MK-677 that would particularly interest bodybuilders who consume highly androgenic substances is hair loss prevention. This is because IGF-1 has been shown to affect the sprouting of hair from the scalp and the entire the hair growth cycle.

Anecdotally, several users of synthetic GH injections and Ibutamoren have reported a faster growth rate of their hair, as well as improved overall hair density.

Of course, since MK-677 increases GH and IGF-1 levels in the body, increases in muscular size and strength tend to be observed in individuals who are already exercising regularly and consuming a proper diet.

It’s not uncommon for Gains of 5-10 pounds of fat-free mass within the first few weeks of MK-677 use are commonly reported – an effect on par with the weight gain commonly seen with the oral steroid, Dianabol.

Is MK-677 Safe?

GH is known to produce certain unpleasant side effects when taken improperly.

You might be wondering…

  • Is MK-677 safer than growth hormone?
  • What side effects does MK-677 have?
  • Do you have to cycle MK-677?

First of all, a common misconception about MK-677 is that it is a SARM, most likely due to the fact that these products are regularly featured alongside each other on supplement vendor websites.

Let’s be clear: MK-677 is not a SARM, and does not carry the same risk profile as exogenous GH injections. In fact, MK-677 does not impact endocrine function in any way, since it does not cause suppression of testosterone [14].

However, one of the most commonly reported side effects from MK-677 is lethargy. In fact, this is to be expected from any substance that increases your GH and IGF-1 levels.

One way to mitigate these effects is by taking MK-677 before bed, instead of at the beginning of the day.

Another common side effect from MK-677, and higher levels of GH and IGF-1 in general, is water retention.

Some muscle pain may also come about as an indirect side effect caused by intracellular water retention, which increases pressure on the joints and muscles [15].

One of the most serious potential side effects from increased levels of GH and IGF-1 in general is elevated blood sugar. GH causes blood sugar levels to go up, which then causes the pancreas release insulin in order to restore blood sugar levels back to normal.

However, overall, several trials with MK-677 have shown almost no serious side effects in participants, both young and elderly. In general, MK-677 is safe to take as long as it is dosed in accordance with the guidelines.

We would suggest starting with a low dose to evaluate how your body reacts to it, and then ramp up from there [16].


MK-677 and Erectile Dysfunction | Overall

In conclusion…

The latest scientific studies show that MK-677 does not cause erectile dysfunction.

In fact, a consistent MK-677 dose of 25mg / ml per day may even benefit bodybuilders and other athletes who are currently suffering from erectile dysfunction.

Now that’s what we’re talking about!

The bottom line is a dose of 25 mg / ml per day or less would be ideal for most athletes and bodybuilders to experience the benefits of this growth hormone secretagogue, without having to deal with a major rise in prolactin levels, which can possibly lead to erectile dysfunction.

In addition, while MK-677 is mostly known for its muscle-building properties, so those wanting to improve their sleep or speed up the healing process for minor injuries will be pleased to notice improvements after using MK-677 consistently.

Are you ready to get started with MK-677?

If so, we highly recommend the brand Chemyo. They put all of their products through rigorous 3rd-party testing, so you know you are getting a premium quality product for your money.

So what are you waiting for?

Get started with Chemyo MK-677 today and watch your gains in the gym (and in the bedroom) shoot through the roof!


  1. Patchett AA, Nargund RP, Tata JR, et al. Design and biological activities of L-163,191 (MK-0677): a potent, orally active growth hormone secretagogue. Proc Natl Acad Sci U S A. 1995;92(15):7001-7005. doi:10.1073/pnas.92.15.7001.
  2. Home. You and Your Hormones. (n.d.). Retrieved May 9, 2022, from
  3. 1997;82(5):1472-9.Gades NM, Jacobson DJ, McGree ME, et al. The associations between serum sex hormones, erectile function, and sex drive: the Olmsted County study of urinary symptoms and health status among men. The journal of sexual medicine. 2008;5(9):2209-2220. doi:10.1111/j.1743-6109.2008.00924.x.
  4. Rajfer J. Growth Factors and Gene Therapy for Erectile Dysfunction. Reviews in Urology. 2000;2(1):34. Pastuszak AW, Liu JS, Vij A. IGF-1 levels are significantly correlated with patient-reported measures of sexual function. International journal of impotence research. 2011; 23(5):220-6.
  5. Palta M, LeCaire T, Sadek-Badawi M, Herrera V, Danielson KK. The trajectory of IGF-1 across age and duration of type 1 diabetes. Diabetes/metabolism research and reviews. 2014;30(8):777-783. doi:10.1002/dmrr.2554.
  6. Becker AJ, Uckert S, Stief CG, et al. Serum levels of human growth hormone during different penile conditions in the cavernous and systemic blood of healthy men and patients with erectile dysfunction. Urology. 2002;59(4):609-614. doi:10.1016/s0090-4295(01)01594-1
  7. Cronkleton, E. (2019, March 29). HGH: Side effects in men and women. Healthline. Retrieved May 5, 2022, from
  8. Smith, R. G. (2005, May 1). Development of growth hormone secretagogues. OUP Academic. Retrieved May 3, 2022, from
  9. Nass R, Pezzoli SS, Oliveri MC, et al. Effects of an oral ghrelin mimetic on body composition and clinical outcomes in healthy older adults: a randomized trial. Ann Intern Med. 2008;149(9):601-611. doi:10.7326/0003-4819-149-9-200811040-00003
  10. Svensson, J., Lönn, L., Jansson, J.-O., Murphy, G., Wyss, D., Krupa, D., Cerchio, K., Polvino, W., Gertz, B., Boseaus, I., Sjöström, L., & Bengtsson, B.-A. (1998, February 1). Two-month treatment of obese subjects with the oral growth hormone (GH) secretagogue mk-677 increases GH secretion, fat-free mass, and Energy Expenditure1. OUP Academic. Retrieved May 3, 2022, from
  11. Smith RG;Sun Y;Jiang H;Albarran-Zeckler R;Timchenko N; (n.d.). Ghrelin receptor (GHS-R1A) agonists show potential as interventive agents during aging. Annals of the New York Academy of Sciences. Retrieved May 9, 2022, from
  12. M. G. Murphy, L. M. Plunkett, B. J. Gertz, W. He, J. Wittreich, W. M. Polvino, D. R. Clemmons, MK-677, an Orally Active Growth Hormone Secretagogue, Reverses Diet-Induced Catabolism, The Journal of Clinical Endocrinology & Metabolism, Volume 83, Issue 2, 1 February 1998, Pages 320–325,
  13. Copinschi, G., Leproult, R., Onderbergen, A. V., Caufriez, A., Cole, K. Y., Schilling, L. M., Mendel, C. M., Lepeleire, I. D., Bolognese, J. A., & Cauter, E. V. (2008, April 9). Prolonged oral treatment with MK-677, a novel growth hormone secretagogue, improves sleep quality in man. Neuroendocrinology. Retrieved May 5, 2022, from
  14. Ian M. Chapman, Ora H. Pescovitz, Gail Murphy, Theresa Treep, Kristine A. Cerchio, David Krupa, Barry Gertz, William J. Polvino, Emily H. Skiles, Suzan S. Pezzoli, Michael O. Thorner, Oral Administration of Growth Hormone (GH) Releasing Peptide-Mimetic MK-677 Stimulates the GH/Insulin-Like Growth Factor-I Axis in Selected GH-Deficient Adults, The Journal of Clinical Endocrinology & Metabolism, Volume 82, Issue 10, 1 October 1997, Pages 3455–3463,
  15. Ishida, J., Saitoh, M., Ebner, N., Springer, J., Anker, S. D., and von Haehling, S. (2020) Growth hormone secretagogues: history, mechanism of action, and clinical development. JCSM Rapid Communications, 3: 25– 37.
  16. Dr. Idiberto Jose Zotarelli Filho, M. S. (2020, May 23). Major approaches the use of GH secretagogue (MK-677) for muscle mass gain in elderly: A brief systematic review. Authorea. Retrieved May 3, 2022, from
Table of Contents
    Add a header to begin generating the table of contents