Phenytoin: i enkelte tilfælde er der, under samtidig behandling med Xeloda og phenytoin, rapporteret om stigninger i plasmakoncentrationerne af phenytoin, som har medført symptomer på fenytoinintoksikation.
Phenytoin: increased phenytoin plasma concentrations resulting in symptoms of phenytoin intoxication in single cases have been reported during concomitant use of Xeloda with phenytoin.