I finished 5 cycles of Gemzar 3 weeks ago. I am still feeling weak with no energy. I have pancreatic cancer and had Whipple procedure in oct,2014. My ca-19-9 was 3500 after surgery and after 15 rounds of gemzar it was down to 103. After my first 4 cycles I started feeling better after 2 or 3 days but now it s been more than 2 weeks and still havn t started feeling any better. My question is, how long can the Gemzar stay in my system and is that why I am so draggy with no energy at all?