Omeprazole 투여시 위산분비 억제능에 대한 CYP2C19 의 영향 = Effects of CYP2C19 Polymorphism on Intragastric Acidity during Omeprazole Administration

다국어 초록 (Multilingual Abstract)

Background/Aims: CYP2C19 has an important role in the catabolism of several proton pump inhibitors. However, the relative contribution of CYP2C19-mediated metabolism varies among the different proton pump inhibitors. We investigate to determine the effect of CYP2C19 genotype status on intragastric pH during dosing with omeprazole. Methods: The subjects were 16 healthy volunteers. Their CYP2C19 genotype status was determined by a polymerase chain reaction-restriction fragment length polymorphism method. Twenty-four-hour monitoring of intragastric acidity were performed on the day without medication and day 4 after omeprazole administration. Results: A single dose of omeprazole significantly decreased 24 hour intragastric acidity (1.7±0.3 vs. 5.1±0.4). Subjects were divided into three groups on the basis of their CYP2C19 genotype status: homozygous extensive metabolizers (Ho-EMs, n=5), heterozygous extensive metabolizers (Ht-EMs, n=6), and poor metabolizers (PMs, n=5). Median 24 hour intragastric pH in the Ho-EM group was 3.1 compared with 5.5 in Ht-EM group and 5.9 in PM group(P<0.05). The median pH during omeprazole administration was influenced by CYP2C19 genotype. On the other hand, the Helicobacter pylori infection did not influence the median intragastric pH during omeprazole administration (p= NS). Conclusions: The effects of omeprazole on intragastric acidity is influenced by the CYP2C19 polymorphism. (Korean J Gastroenterol 2001;38：399-404)