Rectal Absorption of Omeprazole from Suppository Containing an Enteric-coated Tablet.

Omeprazole is a gastric proton pump inhibitor. Since it is commercially available only as an enteric-coated tablet, it is inappropriate for administration to patients for whom it is difficult to swallow tablets or whose intestinal absorption is poor due to gastrointestinal failure. As the rectum is an effective route for the administration for various compounds, the rectal absorption of omeprazole from a suppository containing an omeprazole tablet was studied in healthy male volunteers. The pharmacokinetic parameters were compared with the published data after oral dosing, revealing that the AUCs of omeprazole administered rectally and orally were similar. The rectum was thus conformed to be an effective administration route for omeprazole and the suppository containing an omeprazole tablet to be a practical preparation because it can be prepared rapidly to comprise an accurate drug dosage.