Ronidazole pharmacokinetics after intravenous and oral immediate-release capsule administration in healthy cats.
Ronidazole (RDZ) is an effective treatment for feline Tritrichomonas foetus infection, but has produced neurotoxicity in some cats. An understanding of the disposition of RDZ in cats is needed in order to make precise dosing recommendations. Single-dose pharmacokinetics of intravenous (IV) RDZ and immediate-release RDZ capsules were evaluated. A single dose of IV RDZ (mean 9.2mg/kg) and a 95mg immediate-release RDZ capsule (mean 28.2mg/kg) were administered to six healthy cats in a randomized crossover design. Plasma samples were collected for 48 h and assayed for RDZ using high pressure liquid chromatography (HPLC). Systemic absorption of oral RDZ was rapid and complete, with detection in the plasma of all cats by 10 min after dosing and a bioavailability of 99.64 (±16.54)%. The clearance of RDZ following IV administration was 0.82 (±0.07) ml/kg/min. The terminal half-life was 9.80 (±0.35) and 10.50 (±0.82) h after IV and oral administration, respectively, with drug detectable in all cats 48h after both administrations. The high oral bioavailability of RDZ and slow elimination may predispose cats to neurotoxicity with twice-daily administration. Less frequent administration should be considered for further study of effective treatment of T foetus-infected cats.
Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University, 4700 Hillsborough Street, Raleigh, NC 27606, USA.
Dana N
DN
LeVine
Mark G
MG
Papich
Jody L
JL
Gookin
Gigi S
GS
Davidson
Jennifer L
JL
Davis
Rebecca B
RB
Hayes
D000284:Administration, Oral; D000818:Animals; D000981:Antiprotozoal Agents / Q000008:administration & dosage / Q000493:pharmacokinetics*; D001682:Biological Availability; D002371:Cat Diseases / Q000188:drug therapy; D002415:Cats / Q000378:metabolism*; D018592:Cross-Over Studies; D004305:Dose-Response Relationship, Drug; D007275:Injections, Intravenous; D008297:Male; D008657:Metabolic Clearance Rate; D011529:Protozoan Infections, Animal / Q000188:drug therapy; D011897:Random Allocation; D012385:Ronidazole / Q000008:administration & dosage / Q000493:pharmacokinetics*; D016835:Tritrichomonas foetus / Q000187:drug effects
D000981:Antiprotozoal Agents; D012385:Ronidazole
J Vet Pharmacol Ther. 1991 Sep;14(3):341-3
1744944
J Vet Intern Med. 2010 Jul-Aug;24(4):1003-7
20492492
J Vet Pharmacol Ther. 1992 Dec;15(4):409-15
1487839
J Am Anim Hosp Assoc. 2001 May-Jun;37(3):258-62
11361118
J Vet Pharmacol Ther. 1989 Mar;12(1):46-9
2704060
J Vet Intern Med. 2007 Mar-Apr;21(2):328-31
17427396
Can Vet J. 2009 Jan;50(1):85-7
19337620
J Am Vet Med Assoc. 1999 Nov 15;215(10):1450-4
10579040
J Am Vet Med Assoc. 1989 Aug 1;195(3):365-8
2768064
J Pharmacokinet Biopharm. 1978 Apr;6(2):165-75
671222
J Biol Chem. 1983 Apr 10;258(7):4051-4
6300071
J Appl Toxicol. 2001 Jan-Feb;21(1):15-23
11180276
J Vet Pharmacol Ther. 1990 Sep;13(3):304-8
2231872
Am J Physiol. 1987 May;252(5 Pt 2):H953-62
3578545
J Biol Chem. 1987 Aug 25;262(24):11731-6
2887562
J Vet Intern Med. 2006 May-Jun;20(3):536-43
16734086
Compend Contin Educ Vet. 2009 Aug;31(8):374-81, 390; quiz 381
19866444
J Feline Med Surg. 2003 Jun;5(3):175-81
12765628
J Vet Intern Med. 2007 Sep-Oct;21(5):966-70
17939550
Am J Vet Res. 2007 Oct;68(10):1085-8
17916015
J Am Vet Med Assoc. 2004 Sep 15;225(6):888-92
15485048
J Vet Intern Med. 2003 May-Jun;17(3):304-10
12774970