Florfenicol pharmacokinetics in healthy adult alpacas after subcutaneous and intramuscular injection

Abstract

A single dose of florfenicol (Nuflor®) was administered to eight healthy adult alpacas, at 20mg/kg IM (intramuscular) and 40mg/kg SC (subcutaneous) using a randomized, cross-over design and 28-day washout period. Subsequently, 40mg/kg florfenicol was injected SC every other day for 10 doses to evaluate long-term effects. Maximum plasma florfenicol concentrations (Cmax, measured via high-performance-liquid-chromatography) were achieved rapidly, leading to a higher Cmax of 4.31+/−3.03 μg/ml following administration of 20mg/kg IM than 40mg/kg SC (Cmax: 1.95+/−0.94 μg/ml). Multiple SC dosing at 48hr intervals achieved a Cmax of 4.48+/−1.28 μg/ml at steady state. The area under the curve and terminal elimination half-lives were 51.83+/−11.72μg/ml.h and 17.59+/−11.69 hours after single 20mg/kg IM administration, as well as 99.78+/−23.58μg/ml.h and 99.67+/−59.89 hours following 40mg/kg injection of florfenicol SC, respectively. Florfenicol decreased the following hematological parameters after repeated administration between weeks 0 and 3: total protein (6.38 vs. 5.61 g/dL, P<0.0001), globulin (2.76 vs. 2.16 g/dL, P<0.0003), albumin (3.61 vs. 3.48 g/dL, P=0.0038), white blood cell count (11.89 vs. 9.66 ×10^3/μL, P<0.044), and hematocrit (27.25 vs. 24.88%, P<0.0349). Significant clinical illness was observed in one alpaca. The lowest effective dose of florfenicol should thus be used in alpacas and limited to treatment of highly susceptible pathogens.

Impact of therapeutic and high doses of florfenicol on kidney and liver functional indicators in goat

“…It is speculated that this similarity may be the base to alter this variable in host, when high doses of florfenicol medicated. Outcomes regarding serum protein level coincide with earlier reports [11,17]. The high doses of florfenicol persistently raised the indices of ALP may be associated with high concentration of drug in the blood.…”

“…As indicated urea is the soluble and comparatively less toxic end product of protein breakdown formed from ammonia in liver through urea cycle and if protein- nitrogenous and non-protein nitrogenous byproducts not removed from body, they may finally lead to azotemia [11]. The high doses of florfenicol increased serum creatinine levels which were closely matched with previous studies in pig, alpaca, and in fish [11,14,17]. Creatinine is nonprotein nitrogenous product of creatine (phosphocreatine) produced from muscles.…”

In vitro and in vivo evaluation of an in situ forming gel system for sustained delivery of Florfenicol

“…Florfenicol is characterized by high bioavailability, good tissue penetration, and rapid elimination (Adams et al, 1987;Lobell et al, 1994;Soback et al, 1995;Abd El-Aty et al, 2004;Alcorn et al, 2004;Jiang et al, 2006;Anadon et al, 2008;Koc et al, 2009;Holmes et al, 2012). However, from the point that an animal suffering from disease, it is extremely important that the therapeutic regimen is the most convenient one, especially in terms of drug administration frequency.…”

Influence of Vitamin E on the Disposition Kinetics of Florfenicol after single and multiple oral administrations in Broiler Chickens

“…In both groups the blood samples had been collected at the last day of drugs dosing (5 th day). Blood samples (1ml each) were taken from wing vein just after 5,10,15,30 minutes, 1,2,4,6,8,12,24,48,72 and 96 hrs post-drug administrations. Also all blood samples were left to clot for 30 minutes, centrifuged at 3000 r.p.m.…”