Chemotherapy drug. Computer model of a molecule of the oral chemotherapy drug capecitabine. Atoms are represented as spheres and are colour-coded: carbon (yellow), hydrogen (white), oxygen (red), nitrogen (blue) and fluorine (green). Capecitabine (brand name Xeloda) is used to treat bowel and breast cancers. It can also be used in combination with another drug to treat pancreatic cancer. It belongs to a family of drugs known as antimetabolites. These drugs closely resemble a substance, or metabolite, that is essential for a cell's normal biochemical reactions. By replacing the metabolite, the drug prevents the cells from growing or reproducing.