1988 Volume 3 Issue 4 Pages 387-394
The studies on the mechanism of pharmacokinetic interaction of aluminum hydroxide with new quinolones, ofloxacin, enoxacin and norfloxacin, were performed in rats. New quinolones (20 mg/kg) were administered orally with or without aluminum hydroxide or aluminum chloride (50 mg/kg). Co-administration of aluminum hydroxide induced a significant decrease in Cmax of enoxacin and norfloxacin, and in the AUC values of the three drugs. This effect was enhanced by co-administration of aluminum chloride. The combination of aluminum hydroxide caused a significant increase in the intestinal contents and decrease in urinary excretion of new quinolones. The formation of the stable chelate of new quinolones with Al3+ ions formed from aluminum hydroxide in the same acidic solution as gastric juice was observed. Thus, it is concluded that the co-administration of aluminum hydroxide affects the pharmacokinetics of new quinolones, probably, by the inhibition of the intestinal absorption of new quinolones by the chelate formation of these compounds with Al3+ ions released from aluminum hydroxide in the gastric juice.
