Different Intravenous Administration Techniques for 5-Fluorouracil Pharmacokinetics and Pharmacodynamic Effects

Abstract
The pharmacokinetics after 20min intravenous infusion or a 2min bolus (push) injectiof 5-fluorouracil (500 mg/m2) were studied in 14 colorectal cancer patients. Treatment effects and toxicity related to the administration technique of 5-fluorouracil were retrospectively analysed in 198 colorectal cancer patients. The AUC after bolus injection was 6158 ± 874 μmol/1*min compared to 3 355 ± 428μmol/1*min after short-time infusion of 5-fluorouracil (p<0.01). The mean peak-level after bolus injection was 341 ± 34 M versus 161 ± 17 M after a short-time infusion (p <0.01). Patients receiving bolus injections had significantly better treatment result (32% partial remission) than patients receiving infusion (10% partial remissions, p < 0.001). Toxic side-effects were more frequently encountered after bolus injection but subjective improvement was also more frequently experienced by these patients. Bolus 5-fluorouracil push injection rather than a short-time infusion appears to be the more efficient administration technique.