Hello, I started on Zytiga several months ago. My PSA went from 56 to less than 1 in about 2 weeks. However, my liver enzymes rose beyond acceptable levels and I had to lower the dosage from 1000 milligrams to 750 milligrams per day. For now, things are stable. I have blood drawn every 2 weeks to
to keep an eye on liver enzyme activity. I hope this helps. Philnob.