S c i Pharm
Open Ac c ess
Effec t of Itrac onazole on the
Pharmac okinetic s of
Dic lofenac in Beagle Dogs
Fahad I. AL-JENOOBI
Department of Pharmaceutics, College of Pharmacy, King Saud University, Riyadh 11451, Saudi Arabia.
Sci Pharm. 2010; 78: 465–471
May 19th 2010
Accepted: May 19th 2010
Received: March 13th 2010
This article is available from: http://dx.doi.org/10.3797/scipharm.1003-10
© Al-Jenoobi; licensee Österreichische Apotheker-Verlagsgesellschaft m. b. H., Vienna, Austria.
This is an Open Access article distributed under the terms of the Creative Commons Attribution License
(http://creativecommons.org/licenses/by/3.0/), which permits unrestricted use, distribution, and reproduction
in any medium, provided the original work is properly cited.
The objective of this study was to investigate the potential effect of itraconazole
on the pharmacokinetics of diclofenac potassium in beagle dogs after oral
coadministration. Five male beagle dogs received a single oral 50 mg dose of
diclofenac potassium alone in phase I, and along with a single oral 100 mg dose
of itraconazole in phase II. Blood samples obtained for 8.0 hours post dose
were analysed for diclofenac concentration using a validated high performance
liquid chromatography (HPLC) assay method. The area under plasma
concentration-time curve (AUC0–∞), maximum plasma concentration (Cmax), time
to reach Cmax (Tmax) and elimination half-life (t1/2), were calculated for diclofenac
before and after itraconazole administration. The coadministration of
itraconazole with diclofenac potassium has resulted in a significant reduction in
AUC0–∞ and Cmax of diclofenac, which was about 31 and 42%; respectively. No
statistically significant differences were observed for Tmax and t1/2 of diclofenac
between the two phases. Therefore, it could be concluded that oral
coadministration of itraconazole may have the potential to affect the absorption
of diclofenac as indicated by the significant reduction in its AUC and Cmax in
Interaction • Pharmacokinetic parameters • Plasma concentration • Absorption • HPLC
Effect of Itraconazole on the Pharmacokinetics of Diclofenac in Beagle Dogs 471
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