Effects of meal on the pharmacokinetics of fluoride from oral monofluorophosphate

Abstract

A two-treatment cross-over study was conducted on 8 Caucasian male healthy volunteers aged between 26 and 32 years in order to determine the influence of a standard meal on the bioavailability and pharmacokinetics of fluoride after a single oral administration of tablets containing the equivalent of 10 mg fluoride as sodium monofluorophosphate (Na-MFP, CAS 10163-15-2) in a fixed combination with 300 mg Ca as calcium gluconate and calcium citrate. The meal provoked a significant delay of the appearance of fluoride in blood (from 4 to 11 min), a slowing of the absorption rate, a prolongation of tmax (from 34 to 146 min), a decrease of Cmax (from 369 to 122 ng/ml) and a prolongation of the Mean Residence Time (from 7.1 to 9.1 h). However, the amount of fluoride entering in the systemic circulation was not affected by the meal, as shown by the ANOVA on the AUC and on the cumulated urinary excretion of fluoride in the 48 h following the administration of Na-MFP. It is concluded that appropriate meals do not influence the amount of absorbed fluoride from Na-MFP, and that they modify the rate of absorption with pattern that may improve the safety and possibly also the efficacy of Na-MFP.