title: No effect of short term ranitidine intake on diclofenac pharmacokinetics.
abstract: The pharmacokinetics of diclofenac sodium in healthy volunteers was evaluated to determine if previously repeated doses of ranitidine inhibited the metabolism of the non-steroidal anti-inflammatory drug. Diclofenac sodium 50 mg (tablets) in combination with ranitidine 150 mg (tablets) were administered to 14 healthy human volunteers in a two treatment study design, separated by 5 days in which the ranitidine alone was administrated in single p.o. doses twice daily. Plasma concentrations of diclofenac were determined during a 12 hour period following drug administration. Diclofenac plasma concentrations were determined by a validated RP-HPLC method. Pharmacokinetic parameters were calculated with compartmental and non-compartmental analysis. In the two periods of treatments, the mean peak plasma concentrations Cmax were 1503.9 ng/ml (diclofenac alone) and 1742.5 ng/ml (diclofenac and ranitidine). The time taken to reach the peak, Tmax, was 0.85 hrs, and 0.82 hrs, respectively. The areas under the curve (AUC0-6) were 1479.9 ng x hr/ml and 1650.3 ng x hr/ml, respectively. Statistically insignificant difference was observed in these pharmaco-kinetic parameters of diclofenac sodium when administered alone or after 5 days of treatment with ranitidine. The experimental data did not suggest any consistent effects of ranitidine upon the pharmacokinetics of diclofenac sodium.
authors.affiliation: 3rd Pediatric Clinic, University of Medicine and Pharmacy, Str. Campeni 2-4, Cluj-Napoca, Romania.
authors.forename: Adrian
authors.initials: A
authors.lastname: Leucuţa
authors.forename: Laurian
authors.initials: L
authors.lastname: Vlase
authors.forename: Dorin
authors.initials: D
authors.lastname: Farcau
authors.forename: Mircea
authors.initials: M
authors.lastname: Nanulescu
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000493:pharmacokinetics*; D001682:Biological Availability; D004008:Diclofenac / Q000493:pharmacokinetics*; D004347:Drug Interactions; D006635:Histamine H2 Antagonists / Q000008:administration & dosage / Q000494:pharmacology*; D006801:Humans; D008657:Metabolic Clearance Rate; D011899:Ranitidine / Q000008:administration & dosage / Q000494:pharmacology*
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D006635:Histamine H2 Antagonists; D004008:Diclofenac; D011899:Ranitidine