Disposition Kinetics of Levofloxacin in Sheep after Intravenous and Intramuscular Administration

Table 1

Mean $\pm \mathrm{\hspace{0.17em}\hspace{0.17em}}SD$ plasma pharmacokinetic parameters of levofloxacin ($\mu$g/mL) in sheep ($n=10$) following IV and IM administration at a dose rate of 4 mg/kg b.w.

Parameters	Unit	IV	IM
$\alpha$	${\text{h}}^{-1}$	$2.19\pm 0.17$	—
$k_{\text{a}}$	${\text{h}}^{-1}$	—	$\mathrm{\hspace{0.17em}\hspace{0.17em}}1.39\pm 0.15\mathrm{\hspace{0.17em}\hspace{0.17em}}$
$t_{1/2\alpha }$	$\text{h}$	$0.33\pm 0.12$	—
$t_{1/2(a)}$	$\text{h}$	—	$0.51\pm 0.11\mathrm{\hspace{0.17em}\hspace{0.17em}}$
$\beta$	${\text{h}}^{-1}$	$0.19\pm 0.09$	—
$k_{\text{el}}$	${\text{h}}^{-1}$	—	$\mathrm{\hspace{0.17em}\hspace{0.17em}}0.21\pm 0.04\mathrm{\hspace{0.17em}\hspace{0.17em}}$
$t_{1/2\beta }$	$\text{h}$	$3.29\pm 0.23$	—
$t_{1/2\text{el}}$	$\text{h}$	—	$\mathrm{\hspace{0.17em}\hspace{0.17em}}3.58\pm 0.30$
$V_{(\text{d}(\text{ss}))}$	$\text{l}/\text{kg}$	$0.86\pm 0.23$	$1.02\pm 0.18$
${\text{Cl}}_B$	$\text{L}/\text{h}.\text{kg}$	$0.20\pm 0.05$	$0.19\pm 0.03$
$\text{AUC}$	$\mu \text{g}.\text{h}/\text{mL}$	$21.61\pm 1.24$	$20.24\pm {1.31}^{*}$
$\text{MRT}$	$\text{h}$	$4.26\pm 0.94$	$5.33\pm {1.05}^{*}$
$C_{\max \hspace{0.17em}}$	$\mu \text{g}/\text{mL}$	$12.17\pm 1.73$	$3.10\pm 0.35$
$T_{\max \hspace{0.17em}}$	$\text{h}$	—	$1.64\pm 0.29$
$F$	$\%$	—	$91.35\pm 6.81$

$\beta \mathrm{\hspace{0.17em}\hspace{0.17em}}(k_{\text{el}})$: elimination rate constant; $\alpha \mathrm{\hspace{0.17em}\hspace{0.17em}}(k_a)$: distribution (absorption) rate constant; $t_{1/2\alpha }$: distribution half-life; $t_{1/2(\text{a})}$: absorption half-life; $t_{1/2\beta }\mathrm{\hspace{0.17em}\hspace{0.17em}}(t_{1/2\text{el}}\mathrm{\hspace{0.17em}\hspace{0.17em}})$: elimination half-life; $V_{\text{(d(ss))}}$: volume of distribution; ${\text{Cl}}_B$: total body clearance; AUC: area under the curve from zero to infinity by the trapezoidal integral; MRT: mean residence time; $C_{\max \hspace{0.17em}}$: maximum plasma concentration; $T_{\max \hspace{0.17em}}$: time to peak concentration; F(%): bioavailability; for IM, ($V_{\text{(d(ss))}}=Vd/F$) and ${\text{Cl}}_B={\text{Cl}}_B/F$
${}_{}{}^{*}P<.05.$