Testosterone propionate is a commonly manufactured, oil-based injectable testosterone compound. The added propionate ester will slow the rate in which the steroid is released from the injection site, but only for a few days. Testosterone propionate is therefore comparatively much faster acting than other testosterone esters such as cypionate or enanthate, and requires a much more frequent dosing schedule. While cypionate and enanthate are injected on a weekly basis, propionate is generally administered (at least) every third day. Figure one illustrates a typical release pattern after injection. As you can see, levels peak and begin declining quickly with this ester of testosterone.