Male hormones, such as testosterone, can stimulate the growth of prostate cancer. Therefore, medications that block this hormone can slow the growth of cancer. Therefore, medications that block this hormone can slow the growth of cancer. Typically used after surgery or radiation, hormone suppression therapy can be part of managing advanced prostate cancer. One class of such hormone-blocking medications – the luteinizing hormone – releasing hormone (LHRH) agonists – reduced the testosterone produced by the testicles. Traditionally, this form of therapy was given by injection several times per year. More recently, implants that last 12 months have become available.