Evaluation of the effect of gastrointestinal dialysis by multiple doses of activated charcoal on the toxicokinetics of drug overdose in rats

This study was performed to evaluate the effect of multiple oral doses ofactivated charcoal [MDAC] on the toxicokinetics of intraperitoneallyadministered drug overdoses [phenobarbitone, salicylate, theophylline anddiazepam] in albino rats. Four groups of rats [310 rats] were injected withthe previous 4 drugs, respectively [0 time]. Each group was divided intotest animals [received multiple doses of oral activated charcoal] and controlanimals [received distilled water orally]. Ten animals were sacrificed fromeach group [five from controls and five from test animals] after one hour from zero time, then at different subsequent hours according to every drug groupregimen. Blood samples were analyzed for plasma drug concentration, by enzymemultiplied immunoassay technique for phenobarbitone, theophylline anddiazepam, and fluorescence polarization immunoassay [FPIA] by TDx-FLx for theestimation of salicylate. Significant reduction in half life and enhancedclearance were found in phenobarbitone and theophylline groups. In salicylategroup, the reduction in half life and enhancement of clearance wereinsignificant. No effect of MDAC was found on the plasma concentration ofdiazepam