Effect of Helicobacter pylori infection and acid blockade by lansoprazole on clarithromycin bioavailability

• Published in: Brazilian journal of medical and biological research 2007-03, Vol.40 (3), p.383-389
• Main Authors: Ortiz, R A M, Calafatti, S A, Moraes, L A, Deguer, M, Ecclissato, C C, Marchioretto, M A M, Ribeiro, M L, Bernasconi, G, Pedrazzoli, Jr, J
• Format: Article
• Language: English
• Subjects: 2-Pyridinylmethylsulfinylbenzimidazoles - administration & dosage; Adult; Anti-Bacterial Agents - pharmacokinetics; Anti-Bacterial Agents - therapeutic use; Anti-Ulcer Agents - administration & dosage; Area Under Curve; Biological Availability; Case-Control Studies; Chromatography, High Pressure Liquid; Clarithromycin; Clarithromycin - pharmacokinetics; Clarithromycin - therapeutic use; Cross-Over Studies; Drug Synergism; Helicobacter Infections - drug therapy; Helicobacter Infections - metabolism; Helicobacter pylori; Humans; Lansoprazole; Peptic ulcer; Pharmacokinetics; Proton Pump Inhibitors; Time Factors
• ISSN: 0100-879X; 1414-431X; 1414-431X
• DOI: 10.1590/S0100-879X2007000300014

The effect of proton pump inhibitors and Helicobacter pylori infection on the bioavailability of antibiotics is poorly understood. We determined the effects of 5-day oral administration of 60 mg lansoprazole on the bioavailability of clarithromycin in individuals with and without H. pylori infection. Thirteen H. pylori-infected and 10 non-infected healthy volunteers were enrolled in a study with an open-randomized two-period crossover design and a 21-day washout period between phases. Plasma concentrations of clarithromycin in subjects with and without lansoprazole pre-treatment were measured by liquid chromatography coupled to a tandem mass spectrometer. Clarithromycin Cmax and AUC0-10 h were significantly reduced after lansoprazole administration. In addition, lansoprazole treatment of the H. pylori-positive group resulted in a statistically significant greater reduction in Cmax (40 vs 15%) and AUC0-10 h (30 vs 10%) compared to lansoprazole-treated H. pylori-negative subjects. Thus, treatment with lansoprazole for 5 days reduced bioavailability of clarithromycin, irrespective of H. pylori status. This reduction, however, was even more pronounced in H. pylori-infected individuals.