caa a22 4500 477057861 CHVBK 20180405111351.0 cr unu---uuuuu 170330e19960301xx s 000 0 eng 10.1007/BF00195936 doi (NATIONALLICENCE)springer-10.1007/BF00195936 Omeprazole and lansoprazole are not inducers of cytochrome P4501A2 under conventional therapeutic conditions [Elektronische Daten] [N. Rizzo, J. Scherrmann, C. Padoin, S. Palombo, C. Girre] Objectives: Claims that substituted benzimidazole molecules induce cytochromes P4501A2 are still controversial. This study was undertaken to evaluate their inducing potency under conventional therapeutic conditions. Methods: Twelve healthy non-smoking young volunteers were given 20 mg omeprazole or 30 mg lansoprazole daily, in random order, for 2 weeks, separated by a 3 week wash-out period. We evaluated the CYP1A2 activity by the ratio of the molar urinary concentrations (CUM ratio) of the three end products of the paraxanthine demethylation of caffeine over the molar concentration of a paraxanthine 8-hydroxylation product. Results: This urinary metabolite ratio has previously been shown to be correlated with caffeine clearance. There was slight but non-significant enhancement of the CUM ratio after 2 weeks of treatment with omeprazole (3.62 (1.58) on Day 15 vs 3.09 (1.43) on Day 1), and after lansoprazole (4.26 (2.3) vs 3.65 (2.36)). Similarly, one week of treatment did not significantly alter the CUM ratio after omeprazole or lansoprazole (3.11 (1.58) and 3.28 (1.59), respectively on Day 8). Conclusion: The results show that both omeprazole and lansoprazole in the daily recommended therapeutic doses of 20 mg and 30 mg, respectively, have no influence on the metabolism of caffeine, and therefore no influence on cytochrome CYP1A2 activity. Springer-Verlag, 1996 CYP1A2 nationallicence Omeprazole nationallicence Lansoprazole nationallicence enzyme induction nationallicence caffeine nationallicence Rizzo N. Pharmacie Hôpital Lariboisièrs, Place Ambroise Paré, F-75010, Paris, France aut Scherrmann J. Pharmacie Hôpital Lariboisièrs, Place Ambroise Paré, F-75010, Paris, France aut Padoin C. Pharmacie Hôpital Avicenne, 125, Route de Stalingrad, F-93009, Bobigny, France aut Palombo S. ACTIM Hôpital Fernand Widal, 200 Faubourg Saint-Denis, F-75010, Paris, France aut Girre C. ACTIM Hôpital Fernand Widal, 200 Faubourg Saint-Denis, F-75010, Paris, France aut European Journal of Clinical Pharmacology Springer-Verlag 49/6(1996-03-01), 491-495 0031-6970 49:6<491 1996 49 228 https://doi.org/10.1007/BF00195936 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF00195936 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Rizzo N. Pharmacie Hôpital Lariboisièrs, Place Ambroise Paré, F-75010, Paris, France aut NATIONALLICENCE 700 1- Scherrmann J. Pharmacie Hôpital Lariboisièrs, Place Ambroise Paré, F-75010, Paris, France aut NATIONALLICENCE 700 1- Padoin C. Pharmacie Hôpital Avicenne, 125, Route de Stalingrad, F-93009, Bobigny, France aut NATIONALLICENCE 700 1- Palombo S. ACTIM Hôpital Fernand Widal, 200 Faubourg Saint-Denis, F-75010, Paris, France aut NATIONALLICENCE 700 1- Girre C. ACTIM Hôpital Fernand Widal, 200 Faubourg Saint-Denis, F-75010, Paris, France aut NATIONALLICENCE 773 0- European Journal of Clinical Pharmacology Springer-Verlag 49/6(1996-03-01), 491-495 0031-6970 49:6<491 1996 49 228 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer