title: Oral bioavailability of pantoprazole suspended in sodium bicarbonate solution.
abstract: The bioavailability of pantoprazole when administered as a suspension in sodium bicarbonate solution and as the oral tablet was studied. In an open-label, randomized, two-period crossover study, healthy fasting subjects received either one enteric-coated 40-mg pantoprazole tablet by mouth with 240 mL of water or 20 mL of a suspension prepared from one crushed pantoprazole tablet and 840 mg of sodium bicarbonate solution and administered via a nasogastric tube. Treatments were separated by a 48-hour washout period. Blood samples were collected at intervals up to 24 hours after drug administration for measurement of pantoprazole concentration by high-performance liquid chromatography (HPLC) and estimation of pharmacokinetic values. A separate study was conducted to determine pantoprazole's stability in the suspension for up to three months at 25, 5, and -20 degrees C; concentrations were measured by HPLC. Twelve subjects completed the study. The suspension yielded pantoprazole Cmax values similar to those of the tablet formulation, but the drug was 25% less bioavailable. There was no lag time for the suspension. The suspension was stable for up to two weeks at 5 degrees C and up to three months at -20 degrees C. A suspension of pantoprazole in sodium bicarbonate solution yielded a Cmax similar to that of the tablet formulation, and the drug was quickly absorbed. However, bio-availability was slightly lower with the suspension than with the tablet.
authors.affiliation: Clinical Pharmacokinetics, Wyeth Research, 500 Arcola Road, Collegeville, PA 19426, USA.
authors.forename: Geraldine M
authors.initials: GM
authors.lastname: Ferron
authors.forename: Sherry
authors.initials: S
authors.lastname: Ku
authors.forename: Madelyn
authors.initials: M
authors.lastname: Abell
authors.forename: Mary
authors.initials: M
authors.lastname: Unruh
authors.forename: John
authors.initials: J
authors.lastname: Getsy
authors.forename: Philip R
authors.initials: PR
authors.lastname: Mayer
authors.forename: Jeffrey
authors.initials: J
authors.lastname: Paul
mesh_terms: D053799:2-Pyridinylmethylsulfinylbenzimidazoles; D000328:Adult; D001562:Benzimidazoles / Q000008:administration & dosage / Q000009:adverse effects / Q000493:pharmacokinetics*; D001682:Biological Availability; D018592:Cross-Over Studies; D004355:Drug Stability; D004791:Enzyme Inhibitors / Q000008:administration & dosage / Q000009:adverse effects / Q000493:pharmacokinetics*; D006801:Humans; D008297:Male; D009853:Omeprazole / Q000031:analogs & derivatives; D000077402:Pantoprazole; D054328:Proton Pump Inhibitors; D017693:Sodium Bicarbonate; D013454:Sulfoxides / Q000008:administration & dosage / Q000009:adverse effects / Q000493:pharmacokinetics*; D013535:Suspensions; D013607:Tablets
chemical_list: D053799:2-Pyridinylmethylsulfinylbenzimidazoles; D001562:Benzimidazoles; D004791:Enzyme Inhibitors; D054328:Proton Pump Inhibitors; D013454:Sulfoxides; D013535:Suspensions; D013607:Tablets; D017693:Sodium Bicarbonate; D000077402:Pantoprazole; D009853:Omeprazole