Xeloda is known to induce serious and sometimes fatal
side-effects in patients with low levels of an enzyme called
dihydropyrimidine dehydrogenase (DPD). DPD is the enzyme that
catalyzes the breakdown of Xeloda within the body.
When you have low levels of DPD, Xeloda and its metabolite
5-Fluorouracil can accumulate to toxic levels and cause serious
complications.
Patients can be tested for DPD deficiency by simple laboratory
tests prior to treatment.