| Literature DB >> 28596959 |
María-Aránzazu Martínez1, Irma Ares1, José-Luis Rodríguez1, Marta Martínez1, María-Rosa Martínez-Larrañaga1, Gerardo Isea1, Arturo Anadón1.
Abstract
The pharmacokinetics of pefloxacin after single 10 mg/kg BW intravenous (IV) and oral doses were studied in healthy broiler chickens. For 24 h, serial blood samples were obtained after IV and oral administration. Concentrations of pefloxacin and its major metabolite N-demethyl pefloxacin (norfloxacin) were measured by use of high-performance liquid chromatography. The plasma concentrations-time data were found to fit a two-compartment open model. For pefloxacin, the elimination half-life (t½β) was 8.44 ± 0.48 and 13.18 ± 0.82 h after IV and oral administration, respectively. After single oral dose, pefloxacin was rapidly absorbed with an absorption half-life (t½a) and TMAX of 0.87 ± 0.07 and 2.01 ± 0.12 h, respectively. Maximum plasma concentration (CMAX) was 4.02 ± 0.31 µg/mL. Oral bioavailability of pefloxacin was found to be 70 ± 2%. Pefloxacin was converted to N-demethyl pefloxacin (norfloxacin). This metabolite represented 5% of the parent drug plasma concentrations. The maximal plasma concentration (CMAX) of N-demethyl pefloxacin (norfloxacin) was calculated as 0.19 ± 0.01 mg/mL. The t½β of N-demethyl pefloxacin after oral pefloxacin administration was 10.93 ± 0.80 h. The results indicate that an oral dose of 10 mg pefloxacin/kg BW, every 24 h, should be effective in treatment of the most systemic infections in poultry.Entities:
Keywords: IV and oral dose; PK/PD modeling; broiler chickens; kinetics; pefloxacin
Year: 2017 PMID: 28596959 PMCID: PMC5442175 DOI: 10.3389/fvets.2017.00077
Source DB: PubMed Journal: Front Vet Sci ISSN: 2297-1769
Figure 1Chemical structures of pefloxacin and metabolites.
Figure 2Plasma concentrations of pefloxacin (■) and . Data are expressed as mean ± SD values for eight broiler chickens. Symbols without bars indicate that the SD is within the symbols.
Pefloxacin kinetic parameters for broiler chickens after a single IV and oral administration of pefloxacin (10 mg/kg BW).
| Parameter | IV | Oral |
|---|---|---|
| 14.77 ± 3.50 | 16.33 ± 5.13 | |
| 2.69 ± 0.63 | 1.27 ± 0.16 | |
| – | 18.40 ± 5.33 | |
| α (h−1) | 0.70 ± 0.06 | 0.43 ± 0.07 |
| β (h−1) | 0.082 ± 0.005 | 0.054 ± 0.004 |
| – | 0.80 ± 0.07 | |
| 1.00 ± 0.09 | 1.68 ± 0.36 | |
| 8.44 ± 0.48 | 13.18 ± 0.82*** | |
| – | 0.87 ± 0.07 | |
| 2.36 ± 0.46 | 3.55 ± 0.21 | |
| 1.54 ± 0.33 | – | |
| 0.28 ± 0.03 | 0.16 ± 0.04 | |
| 0.18 ± 0.02 | 0.10 ± 0.01 | |
| 0.32 ± 0.04 | 0.21 ± 0.03 | |
| AUC (mg/h/L) | 53.56 ± 10.09 | 37.71 ± 0.96 |
| – | 70 ± 2 | |
| MRT (h) | 7.94 ± 0.50 | 13.57 ± 0.72 |
| CL (L/h/kg) | 0.19 ± 0.04 | 0.19 ± 0.004 |
| – | 4.02 ± 0.31 | |
| – | 2.01 ± 0.12 |
Values are the mean ± SD, n = 8. Significantly different ***P < 0.001.
A.
–, Not applicable.
.
| Parameter | IV | Oral |
|---|---|---|
| 0.60 ± 0.20 | 1.25 ± 0.13 | |
| 8.02 ± 0.47 | 10.93 ± 0.80 | |
| 0.61 ± 0.19 | 0.24 ± 0.05 | |
| 0.21 ± 0.03 | 0.21 ± 0.02 | |
| 0.51 ± 0.07 | 0.17 ± 0.01 | |
| AUC (mg/h/L) | 2.70 ± 0.33 | 1.93 ± 0.18 |
| MRT (h) | 7.54 ± 0.47 | 13.77 ± 0.86 |
| – | 0.19 ± 0.01 | |
| – | 1.51 ± 0.12 |
Values are the mean ± SD, n = 8.
See Table .
Efficacy predictors (.
| Bacteria | AUC24/MIC (h) | |
|---|---|---|
| 16.08–67 | 150.84–628.5 | |
| 16.08–134 | 150.84–1,257 | |
| 2.01–67 | 18.85–628.5 | |
| 67–134 | 628.5–1,257 | |
| 20.1–67 | 188.55–628.5 | |
| 8.04–16.08 | 75.42–150.84 | |
| 40.2 | 377.1 |
For calculations, the MIC applied values were MIC.