Determination of enrofloxacin in some pharmaceuticals and enrofloxacin bioavailability in pregnant rabbits


Thesis Type: Doctorate

Institution Of The Thesis: Bursa Uludağ University, Sağlık Bilimleri Enstitüsü, Turkey

Approval Date: 2011

Thesis Language: Turkish

Student: İlknur Özdemir

Supervisor: SONGÜL SONAL

Abstract:

Enrofloxacin is a commonly used fluoroquinolone in veterinary medicine. The aim of this study is to detect active substance amounts of enrofloxacin in some trade pharmaceuticals and determination of bioavailability in pregnant rabbits.According to Ministry of Agriculture and Rural Affairs, there are 25 medical companies producing 56 different formulations of enrofloxacin in Turkey. Since there are many different companies and formulations and also lack of control the bioequivalence of those medicals are unknown. In this study, we obtained parenteral formulations of enrofloxacin from different brands. The medicals containing 10 % enrofloxacin were all within expiration date and were from different serial numbers. Samples were diluted to the concentration of 0,5 µg/ml with 0,1 N formic acid and analysed by High Performance Liquid Choromatography (HPLC). When the results were compared with acceptable limits 100 % (± 10), 96 % of the samples were detected as under the limits.The altered physiology of gestation effects drug pharmacokinetics. That is why there should be a necessity of redosing during pregnancy. In this study, we compared the bioavailability of enrofloxacin in non-pregnant and different trimesters of gestation on rabbits. A single dose of 5 mg/kg enrofloxacin was administrated to 24 New Zealand White rabbits by intramuscular route. Blood samples were collected at specific time intervals and plasma concentration were analysed by HPLC. Pharmacokinetics parameters were determined with a PK Solutions computer programme.The pharmacokinetics values of enrofloxacin and its active metabolite ciprofloxacin were compared between non-pregnant and pregnant rabbits. The results of this study showed that pregnancy elevated the absorption t1/2, distribution t1/2, tmax and mean residence time of enrofloxacin. However, pregnancy had no effect on AUC and clearance. It?s determined that pregnancy elevates clearance of ciprofloxacin. It was concluded that pregnancy does not affect the bioavailability of enrofloxacin in pregnant rabbits, but a dosage revision should be considered in the first trimester of pregnancy.