Testosterone Propionate is a single ester testosterone compound and represents one of the most important testosterone compounds every manufactured. When synthetic testosterone was first created it was in its pure form. Simply put there was no ester attached, thereby providing a fast acting compound that would necessarily require a very frequent administration schedule. In 1937 the pharmaceutical giant Schering out of Germany would release the first ester base testosterone in Testosterone Propionate under the trade name Testoviron. The same trade name it would eventually give to its Testosterone Enanthate product. By attaching the Propionate ester to the hormone, this would allow for the hormone’s release time to be controlled and provided a more efficient means in maintaining stable blood levels. Although this was not the first synthetic testosterone preparation created, Testosterone Propionate would become the first commercially available testosterone product. It would also dominate the medical community until the 1960’s and much of the newly born performance enhancing community.
Testosterone Propionate is a pure testosterone hormone. Although synthetic it is a perfect replica of the primary naturally produced male androgen testosterone. By design, the hormone is attached to the Propionate (propionic acid) ester, a small/short ester that enables the hormone’s release time to be controlled. Without an ester, the hormone would disperse and dissipate rapidly post administration. By attaching the ester, this promotes a controlled release and allows the individual to inject the hormone less frequently. Once Testosterone Propionate is injected, the ester slowly begins to detach from the hormone. As the ester is detached the testosterone hormone begins to release into the blood. The half-life of Testosterone Propionate is approximately two days, which is substantially longer than ester free testosterone, which carries a half-life a little less than 24 hours.