M-Sten (Ultradol) bodybuilding’s best kept secret

M-Sten (Ultradol): bodybuilding’s best kept secret?

Methyl-Stenbolone (also known as M-Sten and Ultradrol) is a methylated derivative of Stenbolone, which is a powerful injectable DHT derivative that was never marketed.

M-Sten was sold as a Pro-Hormone for many years despite not being one and being an actual active steroid. Why? Well, Stenbolone was in the list of scheduled Anabolic Androgenic Steroids, and Pro-Hormones were legal during most of the 2000s. By labeling it as a Pro-Hormone, supplement companies were able to sell this powerful oral AAS legally.

After the authorities banned designer steroids from being sold as Pro-Hormones, M-Sten fell from popularity and did not resurface until a few years ago, when some companies cleverly started offering it as a research chemical for laboratory use.

Keep reading to find out how M-Sten works and what you can expect from it.

Benefits of M-Sten

Methyl-Stenbolone is a perfect example of a serious bulking agent that produces little to no water retention due to being non-estrogenic.

It is comparable to Superdrol, meaning that you can expect impressive size gains in short periods of time without bloating up.

Strength will also increase significantly. Despite being a DHT derivative, it does not seem to dry out the joints.

It will not make you as vascular and ripped as other oral DHT derivatives like Winstrol or Anavar, but it will improve the appearance of your physique significantly. Expect insane pumps at the gym.

Anecdotally, some users report feeling very well on it. Unlike other heavy-duty oral bulking agents like Superdrol and Anadrol, M-Sten does not seem to cause users to feel lethargic or “unhealthy” on it.

Side-effects of M-Sten

There is no risk of estrogenic side-effects because M-STEN does not interact with aromatase enzymes or progesterone receptors.

Despite being a DHT derivative, very few people report intense hair loss on it, so it *MAY* be relatively hair-safe for people who suffer from androgenic alopecia.

The most significant side-effects of M-Sten besides the intense testosterone suppression (which is a given with pretty much any AAS), are the dyslipidemia and liver toxicity.

M-Sten will crush HDL (good cholesterol) and increase LDL (bad cholesterol) significantly. It will cause a serious amount of liver damage (similar to Anadrol or Superdrol), so having a good on-cycle therapy protocol in place is crucial.

How to use it

Is M-Sten beginner-friendly? Not at all. I don’t think you should use it unless you have experimented with the vast majority of popular oral AAS because there really is nothing you can get from it that you can’t get from more well-understood and researched oral AAS.

If you have tried most AAS and you want to give this “exotic” AAS a chance, try taking 5 to 10 mg twice a day (for a total of 10 to 20mg a day), for up to 4 weeks at a time.

M-Sten is a fascinating yet largely unknown bulking agent that can provide incredible gains in lean muscle mass in ridiculously short periods of time in exchange for a scary list of potential side-effects. Not something beginners should try!


William Davis

William has been studying and experimenting with bodybuilding pharmacology for over 6 years. After being an independent researcher for all these years, he has decided to share his knowledge with the bodybuilding community through his science-based articles. His approach to enhanced bodybuilding can be summed up in the saying “less is more”, as he believes that prioritizing harm mitigation and looking for ways to maximize the positives is the key to longevity in bodybuilding.