Omeprazole 수지염의 흰쥐와 토끼에서의 위장관내 산도변화에 따른 흡수변화 및 교차시험법에 의한 약물동태연구

Pharmacokinetics of Omeprazole-Resin by Crossover Design and the Variation of Absorption upon pH Change in the Guts of the Rat and the Rabbit.

Pharmacokinetic profiles of omeprazole enteric coated granules including Ramezole(R), Losec(R), omeprazol-Na and omeprazol-resin salt were studied using the crossover design in rats and rabbits. The absorption variance of the preparations at the altered pH condition of the gastrointestinal tract was also studied. After oral administration of four omeprazole enteric coated pellets (10mg/kg) with and without concomitant administration NaHCO3 (5mg/ml, 60mM) in the rats, the differences of absorption rate and extent were evaluated. In the NaHCO3 administration group, the Tmax appeared to be 2~10 times shorter than water administration group, and the Cmax also increased to about 4 times, and the AUC increased to about 2.5 times. Pharmacokinetic parameters of four omeprazole enteric coated pellets in rats showed no statistical significance (ANOVA, P>0.05) in both groups. In the crossover study, the second dosed drug showed 4~5 times increased bioavailability than first dosed drug, which shows the strong carry-over effect of acid secretion of the first dosed drug. The differences of the pharmacokinetic parameters of the two test formulations (Losec(R) and omeprazole-resin) showed no statistical significance.