Absorption and disposition of florfenicol after intravenous, intramuscular and subcutaneous dosing in alpacas.
The objectives of this study were to define disposition and systemic availability of florfenicol in alpacas. Administration of 20 mg/kg doses to 8 male alpacas by i.v., i.m. and s.c. routes was performed by randomized, 3-way crossover design. Clearance and steady state volumes (Vdss) after i.v. injection were 5 ml/min/kg and 775 ml/kg respectively. Mean residence time (MRT) and terminal phase half-life (T1/2λz) were 2.8 h and 2 h respectively. Maximum serum concentrations (Cmax) after i.m. were higher than s.c. administration (p = 0.034). After s.c. dosing, T1/2λz and MRT were greater than after i.m. injection (p < 0.001; p = 0.006 respectively). Mean absorption time (MAT) after s.c. dosing was also prolonged (p = 0.006). Fractional absorption of florfenicol after i.m. and s.c. was not different (p > 0.05). Serum florfenicol concentrations remained >1.0 µg/ml for 20 h after i.m. dosing. Differences in rate and extent of florfenicol absorption after extravascular dosing could influence therapeutic outcomes.
Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Ohio State University, Columbus, OH 43210, USA.
Rebecca L
RL
Pentecost
Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Ohio State University, Columbus, OH 43210, USA.
Andrew J
AJ
Niehaus
Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Ohio State University, Columbus, OH 43210, USA.
Nicholas
N
Werle
Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Ohio State University, Columbus, OH 43210, USA. Electronic address: lakritz.1@osu.edu.
Jeffrey
J
Lakritz
D065567:Absorption, Physiological; D000818:Animals; D000900:Anti-Bacterial Agents / Q000008:administration & dosage / Q000097:blood / Q000493:pharmacokinetics*; D001682:Biological Availability; D002161:Camelids, New World / Q000378:metabolism*; D018592:Cross-Over Studies; D006207:Half-Life; D007273:Injections, Intramuscular / Q000662:veterinary; D007275:Injections, Intravenous / Q000662:veterinary; D007279:Injections, Subcutaneous / Q000662:veterinary; D065586:Intramuscular Absorption; D008297:Male; D065566:Subcutaneous Absorption; D013839:Thiamphenicol / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000097:blood / Q000493:pharmacokinetics
D000900:Anti-Bacterial Agents; C035534:florfenicol; D013839:Thiamphenicol
Absorption time; Bioavailability; Florfenicol; Intramuscular; Intravenous; Pharmacokinetics; Subcutaneous