Andriol is often spoken about as some type of magic product, which to spite being a form of regular testosterone somehow allows for only minimal estrogen conversion. Andriol is a unique oral testosterone product, developed by the international drug company Organon. Andriol is one of the more recently developed anabolic steroids, which first became available in the early 1980's.

This compound contains 40 mg of testosterone undecanoate, based in oil (oleic acid) and sealed inside a capsule. Subtracting the its weight, this equates to a dosage of approximately 25mg of raw testosterone per cap. The design of this steroid is quite different from that of most oral steroids. Drugs administered orally generally enter the blood stream throough the liver. When a steroid compound is given this way without some form of structural protection, it will be quick broken down during the 'first pass'. This process leaves very little steroid intact, basically deactivating the drug.

Adding a methyl group (c-17 AA) to the structure is one way to protect it from this process, however stress is placed on the liver as a result, so the designers of this steroid sought another way to protect the testosterone molecule, with Andriol, this is accomplished by making a form of testosterone that would be absorbed through the lymphatic system. This is done to its high fat solubility brought about by the ester, and its suspension in oil. Having the compound absorbed the way was thought to be very advantageous, as it allows the steroid to bypass the destructive first-pass through the liver.

This should permit the compound to enter the blood stream intact, without the need for a harsh chemic alteration. The ester breaks off once it is in circulation of course, yielding free active testosterone. In design this steroid appears to be that of a completely liver safe and orally active form of testosterone.