With the chemical formula name Androsta-3,5-diene-7,17-dione or more simply known as Arimistane, this is another aromatase inhibitor we’ll be looking at.
This is a unique AI not least because you might have seen it as an ingredient in over the counter supplements which operate in a gray legal area, especially those designed specifically for post cycle therapy use.
Arimistane is one that does not require a prescription and isn’t a breast cancer treatment like most other AIs. It is still used for lowering estrogen levels and that is what makes Arimistane so appealing for bodybuilders and other serious athletes.
My Arimistane PCT guide has been broken down into the following sections:
Table of Contents
What is Arimistane?
Arimistane is an aromatase inhibitor drug with powerful anti-estrogen effects. This is one of the very few AIs which is actually legal without a prescription and can even be bought over the counter in some locations. Despite this, Arimistane is still a prohibited substance by the World Anti-Doping Agency but was only put on the banned list in 2017.
Arimistane is chemically similar in structure to 7-Keto-DHEA, or 7-Ketodehydroepiandrosterone and 7-oxoprasterone which is a prohormone and this often leads to Arimistane being described as a prohormone as well when it is in fact an AI. 7-Keto-DHEA is used to increase the metabolism and thermogenesis (body heat) mainly to aid in fat loss but also to build muscle.
However 7-Keto-DHEA is also a banned substance by world doping bodies. It is often confused with regular DHEA, and this leads to Arimistane also being compared to or even confused with DHEA, so it’s important that athletes are aware that these are all different compounds.
Editor’s Note: For real, NO-BS information on cycling steroids (full suggested dosages, recommended anti-estrogens, and post-cycle therapy) be sure to check out Straight From the Underground (my recommended underground steroid handbook). Everything in this book is based on first hand experience, not theory.
Meanwhile, for those of you looking for an efficacious alternatives to testosterone replacement therapy (TRT), here is my list of effective off-label options for the treatment of low testosterone in men.
Arimistane Benefits (Effects)
Unlike some other AIs, Arimistane is known as a suicide aromatase inhibitor or an irreversible AI, which means you don’t get any estrogen rebound once you stop using it. Arimistane effectively inactivates the aromatase enzyme so the biosynthesis of estrogen can’t take place. It is also known to raise levels of luteinizing hormone (LH), critical for testosterone production.
Additionally Arimistane may lower levels of the stress hormone cortisol which can have a negative impact on testosterone. Studies have shown a clear link in increased cortisol levels resulting in decreased blood testosterone levels.
We know that higher estrogen results in so many dreaded side effects, not the least of which is a decline in your appearance while on steroids and afterwards, especially when it comes to developing that bloated look. Arimistane can be very useful in preventing this by reducing estrogen and helping you achieve a much harder and drier physique.
So while Arimistane is mostly known for its PCT use, we shouldn’t discount this powerful anti-estrogen for on cycle use as well. The fact that it is known to contribute to muscle growth makes Arimistane a useful addition to a growth cycle where it can also provide a boost to testosterone.
A maker of an Arimistane based supplement received a warning from the FDA about using this ingredient in a dietary supplement, stating it is against the law to do so because it does not fall into one of the approved categories of ingredients that are allowed to be in a dietary supplement (these are vitamins, minerals, amino acids, herbs or other botanicals only). As an aromatase inhibitor, Arimistane is not allowed to be included as an ingredient in supplements in the USA.
In summary, makers of Arimistane supplements claim it to be a very potent aromatase inhibitor with the following benefits:
- The ability to block raised levels of estrogen and cortisol hormones
- Provide a boost to testosterone levels
- Increases muscle mass and reduces storage of fat
- Improves recovery
- Dries and hardens the muscles so vascularity is increased
- May also improve the libido
These potential benefits are clearly appealing to bodybuilders and athletes, especially those looking for an AI that does not require a prescription.
Arimistane as a Testosterone Booster
As an aromatase inhibitor that can block estrogen, Arimistane stops testosterone from converting to estrogen and since the steroids you’re using are going to suppress your natural testosterone and bring about an estrogen increase, Arimistane can help bring about a better hormonal balance.
Arimistane will work to lower and control estrogen, and may help those estrogen related side effects like gyno and water retention. Maintaining the right balance between testosterone and estrogen, as a male, will greatly determine what results you’re going to be able to achieve from your workouts and get the most out of the steroids or any other compounds you’re using.
We know testosterone is critical for muscle growth, as well as the entire well being and functioning of an adult male. Likewise, men do need a small amount of estrogen but when it raises to a level that it becomes a dominant hormone in the body, a male suffers and it’s not just your results you’ll be worried about: dreaded side effects come about as a result of estrogen levels that are too high.
Using Arimistane as a possible testosterone booster then can help you avoid these serious issues so your full focus can be on the muscle gains and increased performance that you want to achieve.
Having too much estrogen and low testosterone levels will not only cause you massive problems in gaining muscle, but you will also store more body fat, have decreased strength, endurance and stamina, feel fatigued and depressed, have a low libido, poor sleep, and the list goes on.
Because Arimistane is an aromatase inhibitor it stops the aromatase enzyme from converting your testosterone into estrogen. This is important at all stages of your steroids cycle where you will want to be keeping estrogen in check at all times.
One of the physical effects of high estrogen levels is a bloated appearance from increased water retention. This is not only unsightly and can essentially ruin your physique, but puts you at risk of high blood pressure too. Arimistane contributes to a harder, leaner and drier physique by reducing or eliminating the issue of water retention through the process of controlling the estrogen hormone.
Possibly the most useful role that Arimistane can play is for post cycle therapy where you want to get your testosterone production rolling again so you don’t lose those hard earned gains or suffer dreaded low T symptoms.
Arimistane is excellent for use as a testosterone booster after your steroids cycle, particularly as it’s a suicide aromatase inhibitor and won’t cause a rebound or spike in estrogen levels because it’s effects are irreversible – in other words, it blocks estrogen and keeps it that way and that’s exactly what you need if you’re going to get your testosterone levels back where they need to be.
Arimistane is known to be able raise luteinizing hormone which directly contributes to raising testosterone. And while Arimistane can be powerful when used on its own, it can work well with other ingredients to improve testosterone levels even more and fast track your gains to a higher level.
What are the other ingredients that are sometimes combined with Arimistane in testosterone boosting or PCT supplements? The main ones you will come across include:
- Fenugreek – to naturally boost testosterone and possibly assist with fat burning. This is an ingredient that is found in many natural bodybuilding supplements.
- Horny goat weed – thought to provide some improvement in nitric oxide production which assists with muscle growth and performance.
- Tongkat Ali – can be used to improve hormonal health and potentially give a boost to body composition.
- Tribulus terrestris – maybe the most well known natural testosterone booster, although studies are conflicted on its true effectiveness. Either way, when combined with Arimistane in PCT supplements it might provide that extra boost to your testosterone that is most needed at the time of suppressed natural production.
- L-Citrulline – this amino acid possible improves nitric oxide production as well as blood flow. This can add a performance enhancing effect to an Arimistane based supplement.
These are just a few of the ingredients that you might see coupled with Arimistane in some of the dietary supplements out there which are still using this aromatase inhibitor as an ingredient. All these ingredients might be able to compound upon what Arimistane is able to achieve as an aromatase inhibitor however for the most part their specific benefits on the body are not always scientifically proven or fully understood – nor are the possible side effects from combining Arimistane with one or more other ingredients.
Arimistane for PCT
This is a useful AI for post cycle therapy purposes whether you’ve been doing a cycle of steroids, SARMs or prohormones.
These compounds will usually suppress your natural testosterone to a very low level so without implementing PCT you will suffer from the severe side effects of low testosterone – something no guy wants to experience. Not only that, but you will also lose a lot of any muscle you’ve just gained during your cycle. This is where Arimistane becomes a powerful weapon for restoring testosterone quickly and giving you time for your body’s natural hormone function to start up again.
Arimistane is considered one of the best PCT ingredients to use, both because it’s not difficult to get a hold of and because it’s extremely effective at helping you recover. But this is a compound that you’re more likely to use within a supplement, rather than one you’ll purchase individually like other AIs or SERMs used for PCT.
PCT specific supplements contain not just Arimistane but other ingredients which are known to aid in recovery and maintenance of gains post steroid cycle. Like all supplements, not all of these PCT products are created equally and while some Arimistane based PCT supplements are of high quality, others can be very questionable so it’s critical to research not only all the ingredients contained in the PCT supplement, but the company behind it as well.
In the USA the FDA has deemed Arimistane to not be a legal ingredient to be included in such supplements because it is an aromatase inhibitor, therefore is ineligible to be considered as a dietary supplement in the same way that natural plant extracts and amino acids are. This makes buying Arimistane based PCT supplements more of a challenge than your average bodybuilding supplement.
One of the very few PCT supplements that is easily found containing Arimistane is made by Hi-Tech Pharmaceuticals which is promoted as an all in one PCT formula that limits estrogen and promotes healthy testosterone levels after you’ve finished a cycle of prohormones or steroids. This particular supplement contains no other active ingredients besides 50mg of Androsta 3,5-dien-7,17-dione with two tablets to be taken daily for PCT use.
Users of Arimistane for PCT state that they’ve seen satisfying fat loss and good retaining of gains after a cycle. No side effects to report is a common theme amongst users of this compound which makes it one of the very few compounds that athletes will ever use that comes with very little side effect risk when used at a sensible dosage.
Despite the legal issues that have shut down some other supplement makers from developing and selling Arimistane based PCT supplements, other brands continue to remain available and easily purchased online. This sort of formula makes it simple to acquire a powerful aromatase inhibitor either for PCT or on-cycle usage for people who prefer not to shop on the black market for prescription AIs.
If you do choose to use Arimistane as a stand alone compound instead of as part of a commercial PCT supplement, starting at a low dose is paramount so you can evaluate both the positive effects it has and any potential side effects. For Arimistane PCT usage it is often started at a higher dose at the beginning of the PCT cycle and lowered throughout the cycle.
75mg during week 1, followed by 50mg for the following 2 weeks and doing the final week at 25mg per day should be effective for all but the most hardcore steroid or prohormone users, where you might need to add another 25mg daily to each of these dosages.
If you want to use Arimistane in a cycle for performance enhancement, dosage increases quite substantially so you are getting those performance effects. Starting at 100mg per day for a 6 week cycle will give you a good idea of what this compound can help you achieve. It’s not unheard of for people to raise this dose to 200mg daily but that should only be attempted after you’ve had some experience using Arimistane.
Arimistane Side Effects
Arimistane is considered to be a very side effect friendly compound in that there are little to no reports of side effects, but we must keep in mind that this is not a widely studied compound or one that is at the top of the list to be used by bodybuilders so there is much less sharing of experiences with Arimistane compared with some of the more popular aromatase inhibitors.
In a study on a similar aromatase inhibitor that ran for 8 weeks with 16 resistance trained males, no adverse side effects were reported or found in clinical testing.
Some supplements which contain Arimistane will advise to discontinue use of the product if you experience symptoms like dizziness, increased heartbeat or vomiting. While I haven’t come across any significant reports of people experiencing these side effects, it is a possibility with virtually any compound we take according to how each individual reacts to it – so we can consider these any other symptoms to be low risk with Arimistane, but still to be kept in mind. As always, your dosage will greatly determine your side effects risk so keeping the dose at a moderate level (which still provides excellent benefits) is just common sense.
Does Arimistane block DHT?
Arimistane can block estrogen. DHT (Dihydrotestosterone) is a powerful androgenic hormone which is naturally made from testosterone in the body. So when Arimistane increases testosterone levels, we can expect DHT to also increase. However DHT can also be created by DHEA which is closely related to Arimistane.
One of the main effects of raised DHT in some people is hair loss or male pattern baldness. This is not known to be an issue with Arimistane because while it may increase testosterone, it does not do so at the level that anabolic steroids does and that is where you suffer the androgenic side effects like hair loss. So Arimistane is not a DHT blocker – it is an estrogen blocker.
What is Arimistane good for?
Binding permanently to the aromatase enzyme, Arimistane controls estrogen and prevents the rebound of estrogen that can so often occur with an aromatase inhibitor that is not a suicide AI like Arimistane is. It can help lower estrogen levels while you’re using steroid or prohormone compounds that aromatize, and can help raise testosterone levels during your post cycle therapy period.
During PCT Arimistane is useful for helping retain the gains you’ve made during your cycle which can otherwise be lost because of low testosterone levels; therefore Arimistane is also useful in helping you avoid the countless adverse effects of low testosterone from low energy, muscle loss and fat gain, to libido and mental health.
Is Arimistane legal?
In most countries Arimistane is legal to buy but it is not legal to use in sporting competitions or professional sports of any kind because it is listed as a prohibited performance enhancing substance. The main reason for this is, as an aromatase inhibitor, it lowers estrogen levels so theoretically can help with muscle gain.
This puts Arimistane in the class of a performance enhancing drug according to anti-doping agencies so it’s important to be aware that Arimistane is also used as an ingredient in some PCT supplements so they will also need to be avoided if you are going to be tested.
According to the FDA, it is not legal to include Arimistane in supplements because it is an aromatase inhibitor, not a herb, amino acid, vitamin or other type of ingredient that are allowed to be included in fitness supplements. The FDA actually defines Arimistane as a prescription drug, even though it is not used in the medical field.
Simply the fact that Arimistane is an aromatase inhibitor places it into the category of ingredients which supplement makers are not legally able to include in their products in the USA – however, some still claim to do so although we have found that many of these are in fact a closely related compound similar to DHEA rather than Arimistane itself.
Can you stack Arimistane?
Although not technically considered a stack, Arimistane is often combined with other ingredients in fitness supplements. Many of these other ingredients are often natural ingredients which are known or thought to have a positive impact on testosterone, metabolism, muscle growth and energy.
Some of these natural ingredients which Arimistane is often combined with in supplements include fenugreek, tribulus terrestris, Mucuna Pruriens and amino acids like L-Citrulline.
Most of the supplements that include Arimistane are promoted as natural testosterone boosters or PCT support supplements. Arimistane is not considered to be a legal dietary supplement ingredient by the FDA due to its classification as an aromatase inhibitor.
What’s the best PCT for prohormones?
Sometimes recovery from prohormone cycle can be harsher than steroid cycle. Most of the time I’ll stick to Clomid combined with an AI such as Arimidex. Depending on how much you’ve used and how long the cycle was, I would consider using Nolvadex along with an aromatase inhibitor.
My Conclusion and Recommendation
Arimistane is an aromatase inhibitor that blocks the aromatase enzyme so it can’t convert testosterone to estrogen. It is able to reduce and control estrogen levels, making it easier to control the estrogen related side effects we often see when using steroids and other anabolic compounds that suppress normal testosterone levels and aromatize so testosterone is converted to estrogen; since Arimistane can block this conversion process it is useful for both lowering estrogen and keeping it at the low level it needs to be in males.
If you'd like more real, NO-BS information on using steroids be sure to check out Straight From the Underground (my recommended underground steroid guide). Everything in this book is a real-life experience, not theory.
Meanwhile, for those of you who don't want to use steroids, here is my full list of approved supplements that I feel work (the ones I personally use).