My dad almost went on the Xeloda, or capecitabine. It's an oral pill that turns into the drug called 5-FU in the body. The side effects the doctor told him he could probably expect are:
hand and foot syndrome- possible pain, swelling and redness in the hands and feet,
possibly some mouth sores,
and maybe diarrhea or nausea.
When I went to look for information, it looked like people were having that hand-foot syndrome. http://chemocare.com/chemotherapy/side-effects/handfoot-syndrome.aspx
What I would do is ask your doctor what you might do to ease, or head off some of that. One cancer hospital in the link I posted there gives the suggestion of asking your doctor about taking vitamin B6. Maybe someone will post their experience with that here.