Trenbolone is a synthetic anabolic and androgenic steroid that is available as an ester prodrug. This means that once in the human circulation, it has to undergo modification to the active compound. It was initially used in veterinary medicine and no prescription exists for use in humans. However, it is sold online for human use as an aid for body building.

The steroid has both androgenic and anabolic effects. Once it has been modified in the body, it increases the uptake of ammonium ions in muscles and inherently causes increased protein synthesis. Trenbolone has also been shown to have a potent affinity, similar to that of dihydrotestosterone, to the androgen receptors. It is therefore very potent in its androgenic effects, so effective; it does not require conversion to dihydrotestosterone for these effects to manifest.

It is used for the sole benefits of increasing muscle bulk, maintaining muscle hardness, reducing muscular injury and if this occurs, repairing the muscles at a faster rate. Its use is associated with increased appetite, a small yet beneficial effect for people looking to bulk up. Increasing the vascularity of the muscles and their strength when combined with high intense exercises is also a desired effect.

As a potent anabolic steroid, it is only available in the injectable formulation. It does not suffer the same fate, conversion to estrogen by Aromatase, as other available synthetic steroids. This means that once injected into the body, the enzyme Aromatase cannot deactivate it into estrogen. A larger quantity is thus available to circulate in the body for the desired benefits.

The other effects include the ability to inhibit the action of glucocorticoids. These are steroid hormones that are responsible for catabolic metabolism. This means that the muscle breakdown that usually follows intense exercises is not carried out, therefore maintaining the hard gained muscle bulk.

Some of the other Trenbolone benefits include the fact that it is rapidly cleared from the blood stream. In a week, the steroid is usually no longer circulating in the body. This is beneficial due to reduced contact time for development of unwanted side effects.