I have one annually also since I had cancer. I have no problems with them or the contrast. Lately they haven't been that horrible to drink and they are not requiring me to drink the whole bottle. Just enough to show up on the scans.
The most uncomfortablest part of the whole exam for me is when I am going thru the ct machine it warms my body and it feels like I am wetting in my pants. I know I am not but the heat from the radiation makes it feel that way.
Good luck.