Testosterone enanthate is an oil based injectable steroid, designed to slowly release testosterone from the injection site. Serum concentrations of this hormone will rise for several days and remain elevated for about two weeks. It may take up to three weeks for the action of this drug to fully leave your system. Testosterone enanthate is the most popular prescribed testosterone for treating Hypogonadism and many other disorders that relate to androgen deficiency. Patients enjoy that fact that this drug is long lasting as it cuts down on the number of injections that have to receive.