PT  - JOURNAL ARTICLE
AU  - VERONIKA SCHREIBER
AU  - MARIE KITZMUELLER
AU  - MARTINA POXHOFER
AU  - STEFANIE GINTERSDORFER
AU  - CATHARINA NEUDORFER
AU  - MARIA LICHTNECKERT
AU  - CHRISTIAN DITTRICH
AU  - MARTIN CZEJKA
TI  - Impact of Co-administered Drugs on Drug Monitoring of Capecitabine in Patients with Advanced Colorectal Cancer
DP  - 2014 Jul 01
TA  - Anticancer Research
PG  - 3371--3376
VI  - 34
IP  - 7
4099  - http://ar.iiarjournals.org/content/34/7/3371.short
4100  - http://ar.iiarjournals.org/content/34/7/3371.full
SO  - Anticancer Res2014 Jul 01; 34
AB  - Background: Drug monitoring is a useful tool for obtaining detailed information about the disposition of a drug in an individual patient during chemotherapy. According to the international guidelines, the analytical assay for quantification of a compound in biological samples must be validated. Among a number of parameters, peak purity is an important requirement. Materials and Methods: We analyzed pharmacokinetics in patients who received chemotherapy with capecitabine and up to 10 various co-medications. Results: Out of seven investigated co-administered drugs, we found evidence that the proton pump inhibitor pantoprazole causes peak interferences with capecitabine during high-performance liquid chromatography analysis. Therefore quantification of capecitabine in plasma samples can be inaccurate. Conclusion: We recommend an altered time schedule for co-administered drugs or changing the mobile phase used in the assay.