Beginners Guide to S23: Benefits, Side Effects, and More

You’ve likely heard of S23, which has recently risen to popularity in the SARM world. Users on bodybuilding forums tout the benefits of this non-steroidal muscle growth agent, and S23 is widely hailed as the most potent SARM on the market. Even pharmaceutical GTX, which specializes in hormonal drugs, is investigating S23. But should you believe the hype? 

Like any other SARM, you should be well informed before starting a cycle. In this article, we’re going to discuss everything you need to know before you start. We’ll go over the benefits, side effects, and what results you can expect to see. We’ll also talk about dosing, cycling, PCT supplements, and the most critical aspect—where to purchase high-quality S23.  

If you’re curious to learn more about S23, or if you’re considering taking it, keep reading to find out everything you need to know to make an informed decision.

Key Takeaways
  • 💪 S23 is known as one of the most potent SARMs available, comparable in strength to steroids.
  • 🏋️‍♂️ It is popular for muscle growth, fat reduction, and promoting bone health by targeting specific androgen receptors.
  • 🧪 Despite its benefits, there are no long-term clinical trials on humans to fully understand its effects.
  • 🕒 Users report enhanced endurance, stamina, and increased muscle mass with varied results depending on dosage.
  • 🚫 S23 is also being researched as a potential male contraceptive by temporarily lowering sperm count.
  • 🤸‍♀️ It could increase sexual drive in women, offering an alternative to testosterone for low libido.
  • 🔍 Purchasing S23 is legal for research purposes, though its status can change and it’s banned in competitive sports.
  • 📏 Dosing ranges from 0.5 mg to 50 mg per day, with a recommended cycle of 6 to 10 weeks, depending on bodybuilding experience.
  • 😷 Post Cycle Therapy (PCT) is crucial after an S23 cycle to help restore normal testosterone levels.
  • 🚫 Side effects may include testosterone shutdown, darker urine, and potentially temporary reduction in testicle and prostate size.

About the S23 SARM and what it does

What is S23?

First things first: let’s talk about what S23 is. It is known as a selective androgen receptor modulator, or SARM, that is used to gain muscle mass and reduce body fat, as well as promote bone health. SARMs work by targeting androgen receptors in the body, which makes them release more testosterone. 

You might be thinking that S23 sounds a lot like steroids. Anabolic-androgenic steroids do produce similar results, but there is one key difference between steroids and SARMs. Steroids target every androgen receptor they encounter, whereas SARMs are more specific. They only target muscle and fat tissue, which produces fewer adverse side effects than steroids do. 

Despite being a relatively new SARM, S23 is quite popular in the bodybuilding world. This popularity is mostly thanks to its ability to help you bulk while at the same time reducing fat—the answer to the most significant dilemma that bodybuilders have. It also keeps users from retaining water, another factor in achieving a defined physique. 

Aside from its weightlifting benefits, another reason for the interest in S23 is its potential use as a male contraceptive. This substance caused infertility in rats while they were taking S23, though their reproductive abilities returned to normal once they stopped taking it. In humans, it lowers sperm count enough to be an effective contraception. 

Why do athletes take S23 and what are the benefits?


PHOTO by Pixabay

S23 provides several advantages that make it a sought-after product. Because of how new it is, it’s vital to mention the lack of results of clinical trials on humans. No long-term studies of S23 have been completed, so all the evidence we have is anecdotal evidence from bodybuilders. 

Here are the benefits that they report. Keep in mind that results may vary depending on your diet and training regimen. 

Higher Endurance/Stamina

Being able to endure tougher sessions for more extended periods is what most bodybuilders are after, as the longer and harder you work out, the better results you can expect. Many claim that S23 helps them to do this. 

Users report increased endurance, speed, and stamina, which is consistent with the results in lab rats that saw up to a 50 percent increase in stamina and power growth. Some men also claim that S23 helps them to last longer in bed, too.  

Increased Muscle Mass

Anyone who’s ever tried to put on muscle knows that bulking also means increased levels of body fat. Every bodybuilder’s dream is to build lean muscle more effectively while at the same time reducing fat mass, and S23 appears to have the ability to do just that. 

These better bulking effects do seem dependent on how much of the SARM you take, however, with higher doses equaling more fat-burning capabilities. 

💡 Top S23 Suppliers in 2024

Buy SARMs like S23 from a reputable source. Check out the Verified Sources list to find the best deals on legit SARMs and more.


Though most users aren’t taking it specifically for contraception, S23 is a promising candidate for  effective male birth control. There is much interest in a male pill that can prevent pregnancy without compromising wellbeing and performance, and S23 seems to fit the bill. 

It works by suppressing the hormones that allow for sperm production, which are the luteinizing hormone (LH) and follicle-stimulating hormone (FSH). What makes it so attractive is that the results are temporary. Once men finish taking the course of S23, their fertility returns to normal. 

We don’t recommend using S23 as your only contraceptive measure just yet, however. The wrong dosage can have the opposite effect, triggering sperm production instead of lowering it. Since it hasn’t been approved yet as a male contraceptive, it’s a good idea to use other forms of contraception.  

Increased Sexual Performance in Women

Just the same way S23 is reported to increase sexual drive in men, this 2010 study shows that it may also increase a woman’s desire to have sex. Menopausal women frequently have problems with decreased libido, and doctors often prescribe testosterone as a solution for their low sex drive. At the end of the day, it may end up being a better alternative to testosterone for these women.  

Bone Strength

Finally, S23 is reported to improve bone density, a finding that is supported by a 2008 study. Unlike in muscle building, this SARM appears to improve bone density regardless of how much you’re taking. 

Legal Status

As of this writing, the sale of S23 is currently legal, though SARMs in general are unapproved by the Food and Drug Administration (FDA), and retailers sell it not for human consumption but for research purposes. We recommend reviewing its legality, as this status could change at any time.

Despite being legal to purchase, we do have to mention that SARMs are off-limits to competing athletes. The World Anti-Doping Agency (WADA) has banned them, and the National College Athletic Association (NCAA) has also prohibited its use among athletes. 

How much S23 to take during your cycle


Proper dosing is a critical part of maximizing the benefits of this SARM. So how much should you take, and when should you take it? 

Dosing can range anywhere from 0.5 mg to 50 mg per day, but the recommended range is typically more between 10 mg and up to 20 mg per day. Taking too much is a surefire way to experience adverse side effects, so we advise starting on the lower end of the dosage range, perhaps with 10 mg per day and gradually upping your dosage. 

The half-life is eleven to twelve hours, so you should take it twice per day to obtain the best results. We also recommend consulting a professional to understand the best dosing range for you and your goals. Extreme caution is necessary when dosing, as it’s a potent SARM. Plus, its newness and a lack of human testing make determining exact dosing a challenge.

Read the full S23 dosage guide for more information about dosing S23 correctly.

How long can you cycle S23 at a time?

Cycle Length

Just as critical as knowing how much of this SARM to take is knowing how long you should take it. And just like pinning down an exact dosage can be a challenge, so can determining your cycle length. Ultimately, the right cycle will depend on how much experience you have in bodybuilding. 

If you’re new to this world, it’s a good idea to go conservative, with a cycle that lasts for about six weeks or so. Individuals with moderate to advanced bodybuilding experience can start with an eight- to ten-week cycle, though the average is probably somewhere around eight.

Do you need a PCT for S23?

Post Cycle Therapy

Post cycle therapy, or PCT, is the use of additional supplements that aid your body in returning to a normal state. The question of whether or not to complete a post cycle therapy after using SARMs comes up frequently. 

The answer to this question is a resounding yes—post cycle therapy is an absolute must. PCT is often necessary with SARMs in general, but this practice is even more critical in S23 users because of how much S23 suppresses testosterone function. Completing post cycle therapy ensures that your testosterone production doesn’t shut down completely. 

Using Nolvadex and Clomid is typically how SARMs users aid their body in recovering hormonal balance. A recommended treatment would be to cycle 40 mg of Nolvadex and 50 mg of Clomid for four weeks. 

However, the PCT duration we’ve given is just a guideline and should depend on how long you took S23. Four weeks is typical if you took S23 for longer, but two- to three-week courses are generally sufficient for shorter cycles. If you have any doubts about whether your PCT has been done correctly, having blood work done can reveal any deficiencies. 

What are the side effects of S23?

Side Effects

Now that we’ve discussed the many benefits, it’s time to talk about something equally as important: the side effects. Though there are a lot of advantages to taking S23, it’s not without some side effects, many of which are similar to those of YK11. Here are some things you can expect when taking S23.  

Testosterone Shutdown

Out of all the SARMs on the market, S23 is probably the one that’s closest to conventional steroids. Its formula is so potent that it has different side effects than other SARMs, and one of those is testosterone shutdown. 

We’ve previously said that researchers are curious about it’s potential to act as a male contraceptive because it lowers sperm count. We’ve also already mentioned that its ability to prevent pregnancy is a benefit. However, this testosterone deficiency should also be considered a side effect, as it has unintended, negative consequences for men. 

Many men experience such high testosterone deficiency that they have to supplement with testosterone replacement therapy, or TRT. The reason for TRT is that, for most people, dealing with the effects of having low T levels, even if only temporarily, is not worth it. If you decide not to do TRT while taking S23, you may experience any of the following side effects:

  • Loss of energy and general fatigue
  • Difficulty getting and maintaining erections
  • Loss of libido
  • Decreased levels of motivation 

Testosterone levels return to normal once you’ve finished the S23 cycle, but there are no long-term studies that show what the effects of extended S23 use are.

Smaller Testicles and Prostate Size 

Unlike anabolic steroids, which may increase prostate size, S23 can decrease prostate (and testicle) size. In the same study we mentioned earlier, rats showed reduced prostate and testicle size. These results are to be expected since we just mentioned that S23 shuts down testosterone production. Many users report noticing smaller testicle size while using this SARM. 

Anecdotal evidence suggests that this side effect is merely temporary and that testicles return to their normal size once you have finished the cycle. But again, there are no long-term studies to point to that indicate the effects of extended use of S23 on testicle and prostate size. It’s difficult to state with certainty that using S23 won’t have any impact on your reproductive health. 

Darker Urine

Don’t be surprised if you notice that your urine is darker than normal while taking S23. Dark urine is another reported side effect, but it goes away after you stop treatment. Read more about S23 liver toxicity.


Rage is a typical side effect of conventional steroids, and S23 users have also reported increased aggression. We don’t recommend this SARM if you have anger management issues.  

Hair Loss

One of the lesser side effects is hair loss. Fewer users say that they’ve seen hair loss, but it’s possible to suffer from this issue with S23 use. 

What results can one expect after taking S23?


What can you expect when you take S23? Again, there are no clinical trials to indicate exactly what to expect, just anecdotal evidence. But you can expect results similar to those that you would get with LGD 4033 and Ostarine, such as:

  • Fat loss
  • Muscle growth
  • Increased bone density 
  • Increase stamina 
  • Temporary infertility in men
  • Increased sex drive in women 

These benefits make it highly popular among users seeking an excellent bulking or cutting agent, especially if you pair it with the right exercise program and nutrition. You can expect to be able to go harder for longer, perhaps hit some PRs, and you’ll likely notice some good progress in the gym.  

S23 could be especially useful if you’re preparing for a show, primarily due to the increased stamina users report. This increased stamina leads to greater muscle development, plus the fact that it increases your bone density gives you a stronger foundation that allows you to go harder.

And perhaps the best part is that even if you’re in a caloric deficit, your muscle will be protected. Overall, S23 seems to enhance your efforts in the gym and help you to get a tight physique. 

Where can I buy legit S23 online?

Buy S23

If, after reading all this information about S23, you’re still interested in this SARM, the next question you probably have is how to get your hands on it. 

Generally, you won’t be able to find SARMs over the counter, which means that buying them online is your best bet. In the United States, most people purchase S23 online, which is available from any number of online vendors. If you’re from another country, obtaining S23 may be more complicated. 

In the US, the problem with S23, and SARMs in general, is not availability but instead finding quality sources. This market is unregulated, which means that many companies sell dodgy products whose purity is questionable at best, or they include stuff that isn’t SARMs, as evidenced by this 2017 study . It’s all too easy to get scammed by companies claiming they have the purest product. 

Finding the Right Seller

So how do you, someone who probably doesn’t have an extensive background in science and chemistry, figure out if what you’re getting is the good stuff? There are a few ways to do so. 

The number one criteria is that any company worth its salt will have recent lab results available for view on their website. These results should come from an independent lab since you’ll never get an unbiased report from the company itself. 

Another way to check product quality is by dropping by bodybuilding forums and reading reviews from people who have actually taken the SARM. Doing so can help you get a better idea of whether or not these companies deliver what they say they do. And of course, companies that offer money-back guarantees are more trustworthy than those that do not. 

If you’ve done all this and still aren’t sure, we recommend checking our Verified Source Program, which can help you find SARMs for sale from reputable sellers. 

💡 Top S23 Suppliers in 2024

Buy SARMs like S23 from a reputable source. Check out the Verified Sources list to find the best deals on legit SARMs and more.

On our Verified Source Program list, you’ll find They are a US-based company that manufactures all types of supplements, is one of those reputable sellers that has S23 available for purchase. 

They are included in our Verified Source Program because all their products are tested to ensure the highest quality. They are transparent in displaying test results along with their product descriptions, and they are a generally well-respected brand that won’t scam you. 

Regarding S23, sells 750 mg of the product in a 25 mL bottle. It’s available in liquid and powder forms. 

Before and after pictures of people who used S23

Before / After Pictures

Here is an example of a before and after picture of an individual on an S23 cycle. 

Photo from

Where can I read more S23 reviews?


All it takes is a visit to a bodybuilding forum to hear all about how fantastic this SARM is, and it does seem to be highly effective. It’s renowned for its ability to reduce body fat, while at the same time getting a more sculpted physique. If you’re looking for a hard, defined body, S23 can be a great tool to get you there. 

But despite being a powerhouse new SARM, we still know very little about it. We recommend doing lots of research before starting a regimen and being cautious when using it by making sure to complete PCT and possibly TRT. Understand the potential side effects, especially if fertility is a concern, and only buy from reputable sellers. 

S23 VS Steroids: Which gives better results?

S23 vs Test

Like we mentioned before, S23 is the most “steroid-like” SARM on the market. So why not just use steroids?

Unlike many SARMs, S23 does suppress hormones in the same way steroids do, so in that regard, there’s no benefit to using S23 over steroids. Sure, there are slightly fewer side effects if you’re taking S23, but the overall effect is quite similar. 

If you prefer choosing a substance that is safer and better researched, definitely go with steroids. Remember that S23 is technically not sold for human use but rather research purposes. But if the stigma of steroids is something you prefer to avoid, you may want to give S23 a try. 

Stacking S23 and Test

Stacking S23 with testosterone can lead to bigger gains as testosterone is a powerful hormone that can enhance muscle growth and recovery. When used together, these compounds can work synergistically to maximize gains and provide a more comprehensive approach to bodybuilding. Testosterone can also help offset any potential side effects of S23, such as decreased natural testosterone production.

It is important to note that stacking S23 with testosterone should only be done under the guidance of a healthcare professional and in accordance with applicable laws and regulations.

Commonly asked questions regarding S23 usage


Here are some questions you may have if you’re considering taking S23.

How do I take S23?

S23 is mostly an oral drug, taken by pill or powder, though you can also inject it. Whatever form you take it, the drug absorbs quickly.

What to stack with S23?

Stacking is a common practice in bodybuilders looking to optimize their gains. Many will introduce S23 during the last eight weeks of a twelve-week cutting cycle, which helps them attain the definition they’re looking for. Others stack S23 with MK-677 or GW-501516, which produces a synergistic effect. 

How long does it take to see results?

Most people complete eight-week cycles of S23, and they begin to see results at around four weeks into their cycle. You can speed up the process by sticking with a high protein diet and consistent training plan.


Anecdotal evidence from S23 users promises significant results, like reduced body fat, an increase in lean muscle mass, and amplified stamina and endurance. As a cutting or bulking agent, S23 could help you reach your goals, but you should exercise extreme caution. This SARM is not without undesirable effects, most notably reduced testosterone levels and aggression. 

Despite the fact that testosterone levels seem to return to normal once the cycle is completed, the main issue with this SARM is a lack of clinical studies. There are only a handful of short-term animal studies and no long-term studies that demonstrate how S23 affects the body over time. We still can’t be clear on what the long-term effects of testosterone suppression are.  

Ultimately, the decision about whether or not to try S23 lies with you, especially with the availability of similar SARMS like LGD 4033 and RAD 140. If you feel it could help you reach your goals, take steps to ensure that your experience is as positive as possible. Only buy from a reputable supplier, stay within the recommended dosing range, and complete PCT once you’re finished.  

Literary References

Jones, Amanda & Chen, Jiyun & Hwang, Dong Jin & Miller, Duane & Dalton, James. (2008). 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. 150. 385-95. 10.1210/en.2008-0674. 

Jones A, Hwang DJ, Duke CB 3rd, et al. Nonsteroidal selective androgen receptor modulators enhance female sexual motivation. J Pharmacol Exp Ther. 2010;334(2):439–448. doi:10.1124/jpet.110.168880

Van Wagoner, Ryan M et al. “Chemical Composition and Labeling of Substances Marketed as Selective Androgen Receptor Modulators and Sold via the Internet.” JAMA vol. 318,20 (2017): 2004-2010. doi:10.1001/jama.2017.17069

Chris Jackson
Chris Jackson

Chris Jackson, co-founder of, is a renowned fitness blogger, physique model, and evolutionary bioscience researcher specializing in SARMs (Selective Androgen Receptor Modulators). His extensive work, characterized by cutting-edge research and practical training advice, has made a leading source for accurate, credible information on performance enhancers. With a dedication to improving the understanding and application of SARMs in optimizing human performance, his contributions have not only expanded public awareness but also shaped the conversation around these substances. Chris's pursuit of knowledge and commitment to sharing it continue to inspire many in their fitness journeys.

Have a question? Leave a comment below.

Leave a reply