Pharmacokinetics of imipenem in dogs.
OBJECTIVE
To determine the plasma pharmacokinetics of imipenem (5 mg/kg) after single-dose IV, IM, and SC administrations in dogs and assess the ability of plasma samples to inhibit the growth of Escherichia coli in vitro.


METHODS
6 adult dogs.


METHODS
A 3-way crossover design was used. Plasma concentrations of imipenem were measured after IV, IM, and SC administration by use of high-performance liquid chromatography. An agar well antimicrobial assay was performed with 3 E coli isolates that included a reference strain and 2 multidrug-resistant clinical isolates.


RESULTS
Plasma concentrations of imipenem remained above the reported minimum inhibitory concentration for E coli (0.06 to 0.25 microg/mL) for a minimum of 4 hours after IV, IM, and SC injections. Harmonic mean and pseudo-standard deviation half-life of imipenem was 0.80 +/- 0.23, 0.92 +/- 0.33, and 1.54 +/- 1.02 hours after IV, IM, and SC administration, respectively. Maximum plasma concentrations (Cmax) of imipenem after IM and SC administration were 13.2 +/- 4.06 and 8.8 +/- 1.7 mg/L, respectively. Time elapsed from drug administration until Cmax was 0.50 +/- 0.16 hours after IM and 0.83 +/- 0.13 hours after SC injection. Growth of all 3 E coli isolates was inhibited in the agar well antimicrobial assay for 2 hours after imipenem administration by all routes.


CONCLUSIONS
Imipenem is rapidly and completely absorbed from intramuscular and subcutaneous tissues and effectively inhibits in vitro growth of certain multidrug-resistant clinical isolates of E coli.
Barker
Corrie W
CW
Department of Small Animal Medicine and Surgery, College of Veterinary Medicine, University of Georgia, Athens 30602, USA.
Zhang
Weijiang
W
Sanchez
Susan
S
Budsberg
Steven C
SC
Boudinot
F Douglas
FD
McCrackin Stevenson
M A
MA
D000818:Animals; D000900:Anti-Bacterial Agents / Q000008:administration & dosage / Q000097:blood / Q000493:pharmacokinetics*; D018592:Cross-Over Studies; D004285:Dogs; D024901:Drug Resistance, Multiple, Bacterial; D004926:Escherichia coli / Q000187:drug effects; D006207:Half-Life; D015378:Imipenem / Q000008:administration & dosage / Q000097:blood / Q000493:pharmacokinetics*; D007273:Injections, Intramuscular / Q000662:veterinary; D007275:Injections, Intravenous / Q000662:veterinary; D007279:Injections, Subcutaneous / Q000662:veterinary; D008297:Male; D008826:Microbial Sensitivity Tests
D000900:Anti-Bacterial Agents; D015378:Imipenem