zolodex is goserelin(sp?) is an IV I receive every 3 mo for malignant neoplasm of prostrate with bone metastases: spine, legs, ankles, hip and abdominal area and ribs. this medication retards the mfr testosterone, which seems to fan the fire of my cancer. How long is zolodex effective? What would happen if I discontinued these IV's (which has plenty side effects)? Would it shorten my life? My psa is now around 16. In Feb 2013 it was over 600. When this treatment no longer is effective, how much time do I have??