Testosterone propionate is a slower releasing anabolic steroid with a short half-life. This characteristic allows the user to run short testosterone propionate cycles of 8-10 weeks as optimal peak blood plasma levels are achieved at 2-4 weeks. It is a synthetic androstane steroid derivative of testosterone in the form of 17β propionate ester of testosterone. Testosterone propionate was developed initially by Watson labs, and FDA approved on February 5, 1974. Currently, this drug has been discontinued in humans, but the vet application is still available as an OTC.