S23 SARM: Benefits, Uses, Dosage

S23 is widely believed to be one of the most powerful SARMs, but with great power comes great drawbacks. While S23 can give you massive gains in hypertrophy, strength, and fat loss, the side effects cannot and should not be ignored.

You’ve heard the whispers in the gym – if you’re looking for the most potent SARM on the market (Perhaps barring S4 Andarine) it may be a good idea to look at the S23 SARM. S23 is widely believed to be the most powerful SARM, with effects including muscle gain, fat loss, strength gain, and endurance.

In this article, we’re quickly going to discuss S23, and why it could be of great benefit to you in your lifting career and how to use it. There are, of course some drawbacks, all to be discussed, and even a way to get similar results to steroids…

S23 is known as a nonsteroidal SARM that has been shown to aid in muscle gain but also fat loss. Anecdotally, there is also evidence that S23 can help with strength gain. Like other SARM’s, only certain receptors are bound to, however because S23 is so powerful combined with such a high bioavailability it does have certain drawbacks.

S23 has drawbacks such as particular side effects such as testosterone shut down, testicular shrinkage, and aggression.

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What is S23?

S23 is a Selective Androgen Receptor Modulator (a non steroidal SARM) that as the name suggests, only binds to selective Androgen Receptors in the body. Once these receptors have been bound too, they release a signal to the body that will result in more stimulation and thus, growth. S23 is also currently being tested as a potential male contraceptive (5).

S23 has never been tested on humans, ever, and has only been tested on animals – rats to be particular. In the tests various effects have been found, ranging from muscle gain to fat loss.

How does S23 Work?

The muscles and bones of the human body contains androgen receptors. S23 works by binding to these receptors, stimulating changes similar to that caused by testosterone (4). These changes include but are not limited to hypertrophy of muscle cells, bone density increase, and perhaps even fat loss.

A big drawback of exogenous testosterone (steroids) is of course the fact that testosterone can convert into estrogen via the aromatase enzyme, which can lead to excess fat gain, inflammation, and gyno. Since S23 is not technically a testosterone, it cannot convert into estrogen and normal estrogenic side effects are not to be expected (5).

Conversely, other side effects that are similar to those of testosterone usage are to be expected. S23 is such a powerful SARM with such high bioavailability that side effects such as testosterone suppression can be expected. This is because of the androgenicity of S23 which can also lead to hair loss.

S23 is without doubt one of the most powerful SARMs and should therefor be used very carefully and with great care.

Benefits of S23?

Due to the fact that S23 is such a powerful SARM, it has various benefits. Of course, your actions need to align with your goals in order to reap the best rewards from your S23 usage – this compound won’t magically make you lean while you eat trash all day long, it’s not Tren after all.

Muscle and Strength Gain

S23 binds to androgen receptors within your muscles and will result in an increase in lean mass (3). S23 was initially devised as a method to fight against muscle degradation due to illness, and anecdotal evidence does show that when combined with a caloric surplus S23 can be one of the most intense muscle builders.

Increased Strength

Due to the fact that that S23 not only increases lean mass, but also increases bone density, dictates that this compound is an excellent tool to use in the pursuit of strength gain. In fact, a study in 1998 found that there is a direct correlation between high weight strength training and bone density (1).

Fat Loss

Anecdotally, various users claim that S23 has resulted in fat loss in their usage. Fat loss is obviously only dictated by physics, a caloric deficit. This can be done via eating less, or putting out more energy. S23 resulted in such a great increase in muscle mass, it is often believed that this increased muscle mass caused a corresponding increase in metabolism; hence fat loss (5).

Is S23 Legal?

Like all SARMs, S23 is banned by World Anti Doping Agency (WADA). This means that being tested positive for S23 in any contest that is regulated by WADA, such as the Olympics, will result in dire consequences.

S23 is legally available as an experimental drug, but have not been approved for human consumption. Thus, it needs to be sold as experimental; as it is not approved by the FDA.

Who should use S23?

As with anything from protein powder, to steroids, SARMs (S23 inclusive) will only work if you work. Another thing to consider, is that since S23 can have adverse effects on hormones, it is better to wait past puberty before using it. In fact, wait before you use any SARM or PED.

Lastly, you need to be comfortable and aware of the fact that a PCT period is highly advisable after your S23 cycle completion since there are adverse effects on hormones.

S23 Cycle

You should split your daily dose into 2 servings, as the half life of S23 is 12 hours.

For men, a 8 week cycle could look something like this:

  • Week 1 – 5-30 mg per day
  • Week 2 – 5-30 mg per day
  • Week 3 – 5-30 mg per day
  • Week 4 – 5-30 mg per day
  • Week 5 – 5-30 mg per day
  • Week 6 – 5-30 mg per day
  • Week 7 – 5-30 mg per day
  • Week 8 – 5-30 mg per day

It is not uncommon for inexperienced users to start at a lower dose of 5mg daily, only increasing it after 6 weeks to 10mg daily based on results. More experienced users can opt for higher doses of 30mg daily.

S23 is not advised for female usage (2).

S23 Side Effects

Side effects are pretty common with S23. They are definitely not something to ignore and you should take great care to limit or control these as best you can.

Testosterone Suppression

The reason S23 suppresses your natural testosterone production is simply because it is so powerful. S23 does this by suppressing follicle stimulating hormone (FSH) as well as luteinizing hormone (LH) and follicle stimulating hormone (FSH), similar to that of Steroid side effects. This is also the reason S23 is being researched as a male contraceptive (5).


When combining the anecdotal evidence with the fact that S23 has such a high bioavailability, it is not a far stretch to believe the rumor’s that S23 can cause massive aggression issues.

Hair Loss

Due to the androgenic factor associated with S23, common side effects of androgenic compounds are to be expected. This includes hair loss, often associated with DHT compounds, however S23 is the most potent SARM regarding hair loss.


Due to the suppressive nature of S23, a PCT (Post Cycle Treatment) will be needed. A PCT is needed to restore natural testosterone production, but also deal with any estrogenic side effects of the compound used. Forgoing a PCT after S23 usage is not advised, as this could not only lead to muscle loss, and fat gain but even worse depression.

If you are unsure if your PCT was successful, it might be a good idea to have your bloodwork checked by a medical professional.


Does S23 Work?

Yes. There is tones of anecdotal and even some rat studies to show that taking S23 will have effects on muscle gain and fat loss.

Is S23 Safe?

As all SARMs are all untested on humans, and strictly experimental, safety cannot really be confirmed. Also, S23 does have a lot of side effects associated with it.

Where to Buy S23

S23 is available from a wide range of online sources. However, we strongly suggest using extreme caution when buying it online.
The most trusted and reliable place to buy S23 is Pure Rawz.

S23 vs S4 Andarine

S23 is extremely close to being an ASS in regards to effects not only on muscles, but in regards to side effects. S4 has similar effects, even more so. It is also not advised to take these two together.

S23 vs YK-11

S23 will be the better option since it is a much stronger product. It will also have stronger side effects, thus if you’re new to using SARMs maybe stick to YK-11 (Honestly, even weaker compounds.)

S23 vs Ostarine

Again, S23 will have stronger effects and side effects. Ostarine on the other hand is often regarded as one of the safest SARMs for first timers, and first timers should definitely not be using S23.

Is S23 the Strongest SARM?

“Strongest” is not a scientific term, as it doesn’t have a measurement unit. Bro Science states that S23 is one of the top three strongest SARMs, and should not be used by novice users.

Is S23 Legal?

SARMs are currently not legal to sell for human usage, and can only be sold under “experimental compounds”. All SARMs are also banned by the WADA (World Anti Drug Association).

Still Have Questions?

Drop us a comment down below and one of our expert coaches will respond to it. We’ll also be answering questions on our Instagram!

1.) Tsuzuku S, Ikegami Y, Yabe K. Effects of high-intensity resistance training on bone mineral density in young male powerlifters. Calcif Tissue Int. 1998 Oct;63(4):283-6. doi: 10.1007/s002239900527. PMID: 9744984.


3.) Selective Androgen Receptor Modulators (SARMs): USADA. (2020, July 27). Retrieved from https://www.usada.org/spirit-of-sport/education/selective-androgen-receptor-modulators-sarms-prohibited-class-anabolic-agents/

4) Adachi H, Katsuno M, Minamiyama M, Waza M, Sang C, Nakagomi Y, Kobayashi Y, Tanaka F, Doyu M, Inukai A, Yoshida M, Hashizume Y, Sobue G. Widespread nuclear and cytoplasmic accumulation of mutant androgen receptor in SBMA patients. Brain. 2005 Mar;128(Pt 3):659-70. doi: 10.1093/brain/awh381. Epub 2005 Jan 19. PMID: 15659427.

5) Jones A, Chen J, Hwang DJ, Miller DD, Dalton JT. Preclinical characterization of a (S)-N-(4-cyano-3-trifluoromethyl-phenyl)-3-(3-fluoro, 4-chlorophenoxy)-2-hydroxy-2-methyl-propanamide: a selective androgen receptor modulator for hormonal male contraception. Endocrinology. 2009;150(1):385-395. doi:10.1210/en.2008-0674


Daniel Louwrens BSc PT

Daniel Louwrens BSc PT | Writer

Daniel Louwrens is a well-rounded fitness professional with over 10 years of experience in bodybuilding and fitness. He holds a BSc in Chemistry from the University of Western Cape and is a certified International Personal Trainer and Nutritionist. He is also a skilled bodybuilder and head coach for Muscle and Brawn. With his knowledge and expertise, he provides personalized training, nutrition, and recovery guidance to help clients reach their fitness goals.

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Larnelle Snowden
2 months ago

I actually have some S-23. I’m nervous about using it. I’ve used YK11, MK 2866 and LGD4033.

1 month ago

Dont do IT S23 have me extreme thirst and an epileptic seizure…

Chemical Structure

Mechanism of Action

S23 is a nonsteroidal SARM. It binds to androgen receptors in muscle and bones, stimulating changes similar to that caused by testosterone.

Class of Compound


Street Names



hypertrophy of muscle cells, increases bone density, fat loss

Side Effects and Dangers

Aggression , hair loss, testosterone suppression

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