title: Effects of the association of lansoprazole, clarithromycin and metronidazole for helicobacter Pylori eradication therapy, measured by the 13C Aminopyrine breath test.
abstract: BACKGROUND
  Lansoprazole (LAN) is a proton pump inhibitor drug (PPI) metabolized by the P-450 liver cytochrome (CYP-450) system. LAN is used in association with antimicrobial agents in Helicobacter pylori (HP) eradication therapy. The 13C-Aminopyrine breath test (ABT) is a non-invasive tool exploring liver CYP-450 metabolic activity. Since pharmacological interactions may occur during PPI administration, we attempted to evaluate possible interference with liver CYP-450 activity during HP eradication therapy.
  
  
  METHODS
  Fourteen HP positive patients received LAN (30 mg b.i.d.), clarithromycin (500 mg b.i.d.) and metronidazole (500 mg b.i.d.) for one week. Prior to therapy, and at day 8, each patient underwent 13C-ABT. The 13CO2 concentration in breath samples was measured every 15 minutes from t0 to t120. Results are expressed as cumulative percentage of the administered dose of 13C recovered over time (% 13C dose cum), and as a percentage of the administered dose of 13C recovered per hour (% l3C dose/h). Comparisons were carried out by the Wilcoxon test. Data are presented as mean +/- SD.
  
  
  RESULTS
  At day 8, mean ABT was no different from baseline values, both considering % 13C dose cum and% 13C dose/h at each sampling time (e.g.,% 13C dose cum120 which is the most expressive value of the parameters taken into consideration, baseline vs day 8: 10.88 +/- 3.81 vs 10.13 +/- 3.57).
  
  
  CONCLUSIONS
  These results show that LAN administration and the concomitant use of antimicrobial drugs during HP eradication therapy do not seem to be associated with significant modifications in liver CYP-450 activity.
authors.affiliation: Gastroenterology Unit and Postgraduate School of Gastroenterology and Digestive Endoscopy, Department of Internal Medicine, University of Genoa, Genoa, Italy.
authors.forename: Federica
authors.initials: F
authors.lastname: Malfatti
authors.forename: Edoardo
authors.initials: E
authors.lastname: Giannini
authors.forename: Testa
authors.initials: T
authors.lastname: Emanuela
authors.forename: Simone
authors.initials: S
authors.lastname: Polegato
authors.forename: Elena
authors.initials: E
authors.lastname: Podestà
authors.forename: Alessandra
authors.initials: A
authors.lastname: Fumagalli
authors.forename: Tiziana
authors.initials: T
authors.lastname: Cotelessa
authors.forename: Bruno
authors.initials: B
authors.lastname: Chiarbonello
authors.forename: Michele
authors.initials: M
authors.lastname: Bellotti
authors.forename: Federica
authors.initials: F
authors.lastname: Botta
authors.forename: Sara
authors.initials: S
authors.lastname: Milazzo
authors.forename: Roberto
authors.initials: R
authors.lastname: Testa
mesh_terms: D053799:2-Pyridinylmethylsulfinylbenzimidazoles; D000328:Adult; D000367:Age Factors; D000368:Aged; D000632:Aminopyrine / Q000737:chemistry / Q000378:metabolism*; D001944:Breath Tests; D002247:Carbon Isotopes; D017291:Clarithromycin / Q000627:therapeutic use*; D005260:Female; D016481:Helicobacter Infections / Q000188:drug therapy* / Q000382:microbiology*; D016480:Helicobacter pylori / Q000187:drug effects / Q000502:physiology; D006801:Humans; D064747:Lansoprazole; D008297:Male; D008795:Metronidazole / Q000627:therapeutic use*; D008875:Middle Aged; D009853:Omeprazole / Q000031:analogs & derivatives* / Q000627:therapeutic use*; D012727:Sex Characteristics
chemical_list: D053799:2-Pyridinylmethylsulfinylbenzimidazoles; D002247:Carbon Isotopes; D000632:Aminopyrine; D064747:Lansoprazole; D008795:Metronidazole; D017291:Clarithromycin; D009853:Omeprazole