Andriol-bannerNo matter how strange it may sound, most pharmaceutical companies focus primarily on achieving the best anabolic power of steroids, and they tend to forget about working on their side effects. That was not the case with Organon when they tried to create an oral testosterone product that would not posses the undesired side effects that are inherent to most oral steroids. The result of such work is testosterone undecanoate, most commonly known as Andriol – and it is quite an interesting result.

Since it was developed in the beginning of 1980’s, andriol is a very modern anabolic androgenic steroid (AAS). It was developed in an attempt to create a steroid that would be more convenient to use and safer in terms of side effects.


AndriolAs its name suggests, testosterone undecanoate is an esterified version of testosterone, and it therefore has a very high fat solubility. 40 milligrams (mgs) of andriol are mixed with oil in capsules, of which only 25 mg are pure testosterone. In the beginning of production, it was dissolved in oleic acid, which was later replaced with caster oil combined with propylene glycol laurate (commercially renamed to Andriol Testocaps). Nevertheless, only the shelf life of the product changed.

Liver toxicity

The fact that testosterone undecanoate is esterified and comes dissolved in oil capsules has a huge advantage over other oral steroids. It completely avoids any contact with the liver because after ingestion, andriol gets absorbed by the lymphatic system and the small intestine. Usually, other oral steroids get broken down by the first liver pass, leaving only a small fraction of active substance to be absorbed by the system. The common solution for this problem is adding c17 alpha alkylation (c17aa) to the oral steroids, which protects them from the first liver pass. However, this puts the liver under considerable stress. On the other hand, andriol does not come into contact with the liver, and the first liver pass is not an issue for this steroid. Therefore, it is not necessary to add the c17aa group, which makes andriol non-toxic to the liver.

Bioavailability and effectiveness of andriol

Andriol may look like a marvel of scientific achievements, as it does not affect the liver. However, there is also another side to this story. Most users report that it’s extremely mild; as a result, if you are to achieve noticeable gains, the doses have to be very high – 240-400 mg daily. Even with high doses, bodybuilders usually report an average gain of 5 lbs per cycle of andriol, which, lets face it – is very little compared to other steroids.

Various scientific studies have determined that the mildness of andriol comes from varying bioavailability (BA). This means that the testosterone contained in the capsules does not make it into the blood stream in high enough volume. In various studies done with andriol, users were given the same dose of the drug, and yet they had different testosterone levels. This led the scientific community to the conclusion that the variable testosterone levels are a result of individual differences in metabolism and absorption rates. Moreover, these differences may even take place in each separate subject on a daily basis due to the fluctuations of metabolism.


Major drawbacks

Health wise, andriol is a very safe steroid, perhaps even the safest steroid out there. However, when it comes to being practical, dosing and pricing is a huge problem. Andriol is a very expensive steroid, and it becomes even more expensive when one takes the high dosages that are needed to notice any results. In addition, andriol has to be taken every 3 to 5 hours, which is not practical.

Due to its mildness, really few bodybuilders consume testosterone undecanoate, or at least do so without stacking it with some other steroids. Only those looking for a very mild and safe product use andriol, and at times are even satisfied with the results it renders. One must keep in mind, that not all the substance might be absorbed by the body, but some testosterone still enters the system, and therefore the user will inevitably experience certain mass gains. But yet again, the cost of andriol is a huge drawback for many.


It is worth mentioning that, in a way, testosterone undecanoate is a very safe buy (except for your wallet). It is very hard to replicate, and hence the probability of getting a fake form of andriol is very slim. Besides, if certain guidelines are followed, it is pretty easy to identify the real product.

Side Effects

clomidSome people get misled by the assumption that andriol has very few, if any at all, estrogenic side effects because it is esterified, but this is not the case. By no means do the esters affect the ability of testosterone to aromatize, since they only change the release rate of the active substance. Most probably, the small amount of testosterone absorbed by the body is the responsible for the poor aromatization rates of andriol. No matter the reasons, it is a fact that estrogenic side effects are very unlikely with testosterone undecanoate, and only excessive dosages can lead to minor estrogenic side effects.

While testosterone undecanoate can affect the Hypothalamus-Pituitary-Testicular-Axis (HPTA), it’s very mild. Nonetheless, it is recommended you do a post cycle therapy (PCT) with such drugs as Clomid and Nolvadex.

In regards to hepatotoxicity, which is one of the most common side effects of oral steroids, andriol shines once again. Since it is absorbed by the lymphatic system and is not broken down during the first liver pass, testosterone undecanoate does not stress the liver. Furthermore, in several studies prolonged cycles of andriol did not exert any noticeable influence on the liver function whatsoever.

What is really noteworthy of testosterone undecanoate, is that it has more positive side effects than negative side effects. Apart from its mild anabolic and androgenic activity, it can reportedly improve lipid profiles and cholesterol levels.

Half life

According to studies, andriol’s half life stands somewhere between 3 and 7 hours. Though, andriol’s active life is less than 8 hours, and it peaks the testosterone levels just two hours after taking it.

Dosages and use

andriol-testocapsDosages below 240 milligrams (mg) seem to be pointless because according to multiple reports, such amounts of andriol do not provide any obvious results. The average daily dose athletes take is 320-400 mg (8 to 10 caps), and thanks to its mildness in terms of side effects, some even take up to 600 mg per day.

As mentioned above, due to its short active life and fast testosterone peaks, andriol should be taken frequently during the daytime. The best thing is to take this steroid every two hours, but that schedule is quite inconvenient for many. Most users opt for taking it every four hours.

Since the lymphatic system and the small intestine are involved in the absorption of andriol by the organism, best results can be achieved by taking it during the meals.

If you are expecting serious mass and strength gains, and you want to see those happen fast, another steroid will be a better choice. However, if you are looking for a mild steroid and side effects are a major concern to you – andriol is the way to go. Furthermore, the rapid increase in testosterone levels after administration makes testosterone undecanoate a pre-workout supplement to keep in mind.


Although its name strongly resembles that of Anadrol, andriol is actually a complete opposite of the bulking champion of steroids. While anadrol offers extreme results, andriol is very mild. On the other hand, andriol barely has any side effects, and none of them are a threat to health, whilst anadrol is a steroid with lots of prominent negative side effects.

Andriol is a very special steroid, which stands apart from the rest of AAS. Its best quality is the mildness and safety – it can even be said that it does not have any side effects, even at very high dosages. However, testosterone undecanoate is a very expensive steroid that gives very poor results in comparison with other anabolic androgenic steroids. Even such shy results as a 5 lb gain per cycle will have a very high financial cost to the user.

Another downside of andriol is that its effectiveness is very unstable, both between subjects, and within subjects. The lymphatic path of absorption has proven to be very dependable on individual metabolism rates and fluctuations, which can even change many times during the day.

All in all, it is a good choice for those who are weary of steroids’ side effects, and who do not expect serious gains in muscle mass. Another thing to keep in mind, is that apart from anabolic and androgenic effects, andriol seems to be very beneficial in such health aspects as lipid profiles, blood pressure, and cholesterol levels.


View Article Source
SOURCES: “Andriol (Testosterone Undecanoate)”

The University of Tennessee, Health Science Center, Division of Endocrinology, Diabetes and Metabolism: “PATHOPHYSIOLOGY COURSE,ENDOCRINE MODULE:Male Gonadal Disorders ”

© 2015, LLC. All rights reserved.

Leave a Reply