In:
American Journal of Veterinary Research, American Veterinary Medical Association (AVMA), Vol. 65, No. 6 ( 2004-06-01), p. 835-840
Abstract:
Objective —To characterize the pharmacokinetics of
zidovudine (AZT) in cats. Animals —6 sexually intact 9-month-old barrier-reared
domestic shorthair cats. Procedure —Cats were randomly alloted into 3
groups, and zidovudine (25 mg/kg) was administered IV, intragastrically (IG), and PO in a 3-way crossover
study design with 2-week washout periods between experiments. Plasma samples were collected for 12
hours after drug administration, and zidovudine concentrations were determined by high-performance liquid
chromatography. Maximum plasma concentrations (C max ), time to reach C max (T max ), and bioavailability
were compared between IG and PO routes. Area under the curve (AUC) and terminal phase halflife
(t½) among the 3 administration routes were also compared. Results —Plasma concentrations of zidovudine
declined rapidly with t½ of 1.4 ± 0.19 hours, 1.4 ± 0.16 hours, and 1.5 ± 0.28 hours after IV, IG, and PO administration,
respectively. Total body clearance and steady-state volume of distribution were 0.41 ± 0.10
L/h/kg and 0.82 ± 0.15 L/kg, respectively. Mean T max for IG administration (0.22 hours) was significantly
shorter than T max for PO administration (0.67 hours).
The AUC after IV and PO administration was 64.7 ± 16.6 mg·h/L and 60.5 ± 17.0 mg·h/L, respectively,
whereas AUC for the IG route was significantly less at 42.5 ± 9.41 mg·h/L. Zidovudine was well absorbed
after IG and PO administration with bioavailability values of 70 ± 24% and 95 ± 23%, respectively. Conclusions and Clinical Relevance —Cats had
slower clearance of zidovudine, compared with other species. Plasma concentrations of zidovudine were
maintained above the minimum effective concentration for inhibiting FIV replication by 50% (0.07µM
[0.019 µg/mL] for wild-type FIV clinical isolate) for at
least 12 hours after IV, IG, or PO administration. ( Am
J Vet Res 2004;65:835–840)
Type of Medium:
Online Resource
ISSN:
0002-9645
DOI:
10.2460/ajvr.2004.65.835
Language:
Unknown
Publisher:
American Veterinary Medical Association (AVMA)
Publication Date:
2004
detail.hit.zdb_id:
2056942-7
SSG:
22
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