I had been on zytiga for just over 5-months in the first half of 2012. As strange as it might seem, there is no typical reaction or side effects of most of these meds.
But, with that said, my side effects were:
1) all moderate except -
2) my appetite completely disappeared.
3) lost well over 40-pounds in 5-months.
And my PSA results are shown below:
Notes: I am on my fourth chemo (or similar). Two have not worked for me - both were oral. Two have worked for me. See below for the taxotere results.
My current chemo treatment is 6-treatments of Jevtana over 18-weeks - then less than a week ago, a 7th treatment which is being called a maintenance treatment (every 4-weeks for the next three months).
My PSA on Jevtana came down from 83.09 in early October of 2013 to 12-days ago with a PSA of 15.49!
Again - we all seem to react differently to different meds.
Good luck on your zytiga.
Peace and wellness
Rob & Gizmo
Initial Dx of PCa in 2003/2004
Radiation (5x5wks) & Brachytherapy (96 seeds) in 2004
Low PSA for 6-years then Casodex briefly
Lupron from 2011 to current
Zytiga 2012 (5-months) - PSA increase
Prednisone & Xgeva from 2012
Taxotere - August 2012 (30-weeks) - PSA from 54+ to 12+
No chemo (8-wks) - PSA to over 23
Xtandi - June to Aug - 2013 - PSA increase
Jevtana + Lexapro - from October 2013