Ostarine: Important Facts You Must Know About MK-2866

Table Of Contents

What Is Ostarine?

Ostarine is a selective androgen receptor modulator (SARM); you might also know it as MK-2866 or Enobosarm. It is an investigational compound that is still being researched.

It is one of the most popular SARMs because it’s said to be a mild compound with the most scientific research available.

Despite not being safe for consumption, many bodybuilders and athletes have turned to SARMs such as Ostarine to help them improve performance.

In this article, we will provide you with several facts on MK-2866 supported by the latest scientific data.

Ostarine MK 2866 chemical structure

Due to the limited data available on Ostarine (MK-2866), we recommend steering clear from this compound. We are simply providing information based on research and user experiences as requested by our following.

What Research Says About Ostarine (MK-2866)

Compared to other selective androgen receptor modulators, Ostarine is ahead of them as a clinical candidate.

There’s a lot of scientific research available on this compound, and therefore, it has gained the attention of bodybuilders and other athletes.

Based on the research, we will provide you with some of the effects this compound can have.

1. Stimulates Muscle Growth

Ostarine was developed to help treat muscle-wasting conditions (1). Therefore, it has the capability to help preserve as well as build lean muscle mass.

Clinical trials show that MK-2866 can significantly enhance lean muscle mass at low dosages. (2). Test subjects gained between 1.3 to 1.4kg over three months at 3mg per day.

A more recent study on Ostarine has shown it to improve muscle tissue in rats at dosages of 0.4 and 4mg (3).

With this data available, it’s safe to say that it is possible that this compound significantly stimulates the growth of muscle tissue. This is why many people often compare it to steroids and prohormones.

2. Improves Bone Healing

Selective androgen receptor modulators such as Ostarine might improve the health of bones, as rat studies have shown promising results (4).

The main improvements during these rat studies are bone mineral density and bone volume density (5). This means it could be an interesting compound to explore to combat osteoporosis.

With that said, MK-2866 has to be researched more thoroughly, and we advise steering clear from SARMs until more safety information becomes available.

3. Improved Insulin Resistance

Besides increasing muscle growth and bone density, Ostarine (MK-2866) is also said to have the ability to improve insulin resistance (6).

During some studies, lowered blood glucose levels were also observed. Increased insulin sensitivity can have multiple benefits, such as enhancing fat loss and fewer sugar cravings.

The Best Ostarine Dosage For Research

When we look at the Ostarine dosage data in front of us, the first thing we can point out is that it has good bioavailability. That means that it’s absorbed rapidly, and the effects can show quickly.

During the clinical studies, the dosage of Ostarine was between 1 to 3mg per day. These dosages were well tolerated and showed significant changes in lean body mass.

Please see the image below to see what results from these low dosages of ostarine can have.

Ostarine dosage research

At a dosage of 3mg per day, there are massive changes compared to the rest. When we look at anecdotal user experiences of people who have tried Ostarine, they typically run it 10 to 20mg per day.

Most users stick to the dosage protocol of 10 to 20mg per day because they say it’s more than enough to get the desired results.

With higher dosage, they also experienced more unwanted effects such as hormone suppression, headaches, and more. That is why a post cycle therapy will be needed after a cycle with MK-2866.

Users point out that it is a lot weaker than, for example, RAD 140.

Do You Need PCT For Ostarine?

Yes, running a SARMs PCT after a cycle of ostarine is an absolute must. It’s a must because it has been shown that MK-2866 suppresses your natural testosterone production.

That means after a cycle is finished, your body will require help to get those hormones up and running again.

Not using one can have many negatives, and it will take much longer for you to recover.

The best product to use as a PCT after a cycle with SARMs is Rebirth PCT.

Rebirth PCT by Huge Nutrition contains all the essential ingredients you should look for in a sarms post cycle therapy supplement. It has Arimistane and many other effective compounds in it.

Make sure to get yourself at least one or two bottles to use after your cycle.

Is Ostarine Safe And Does It Cause Side Effects?

Ostarine is still undergoing research, and therefore limited data is available on its safety. Even though clinical data shows that it was well tolerated at moderate dosages, we cannot conclude that it’s safe to use.

Clinical research doesn’t tell us much about the side effects Ostarine can cause, which is why we have turned to user reports to find out more.

During our research, we quickly concluded that the use of MK-2866 does come with side effects. The following side effects have been reported by users that have experimented with Ostarine:

  • Testosterone suppression
  • Fatigue and mood swings
  • Gynecomastia
  • Reduced libido and sex drive
  • Acne
  • Hair loss
  • Joint pain
  • Increase in estrogen 
  • Headaches
  • Lower back pain

These side effects are very comparable to the adverse effects caused by steroids such as Dianabol. Many users think that this compound is free of negatives, but according to user experiences, it is definitely not.

Yet, many still use it for its performance-enhancing properties. It is crucial to research these SARMs further to fully understand their mechanism of action.

Post cycle therapy is a must when running SARMs such as this one. Therefore you must stock up on Rebirth PCT to help you recover after the cycle is done.

Do We Recommend Ostarine?

Because Ostarine is still an investigational compound, we do not recommend it. We’re all about enhancing performance, but it has to be done responsibly.

And with using Mk-2866, you are putting your health at risk since minimal information is available on the (long term) side effects.

We do not know enough about this compound to be able to recommend it to you. But, for those of you that are looking for something potent, we’ve got an alternative.

ostarine alternative

Check out Huge Ecdysterone. Research has shown that the active ingredient, Ecdysterone, is even better than some SARMs (1).

That means increased lean muscle mass, strength, and accelerated recovery, similar to Ostarine.

But Ecdysterone doesn’t carry the side effects, and you won’t have to worry about running a post cycle therapy.

The bottom line, it’s a much better option, and you won’t have any adverse effects. You can check it by visiting the official product page.

If you do wish to proceed with an Ostarine cycle, make sure to have your PCT on hand for when you need it. We advise Rebirth PCT by Huge Nutrition because it’s the most stacked post cycle therapy your going to find.


Ostarine is a promising SARM that is still being researched for its potential benefits.

Even though it is still under investigation, many athletes use it to enhance their performance and physique.

The long term side effects are unknown, which is why we don’t feel comfortable recommending a product like this to our audience.

We advise looking at Huge Ecdysterone instead, which is said to be a better alternative than many SARMs.

If you wish to share your experience with MK-2866, you can leave a comment on this article.

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