V. Dumka, A. Srivastava
Feb 5, 2007
Citations
1
Influential Citations
24
Citations
Journal
Veterinary Research Communications
Abstract
Levofloxacin ((−)-9-fluoro-3-methyl-10-(4-methyl-1-piprazinyl)-7-oxo-2,3-dihydro-7Hpyrido [1,2,3-de]-[1,4]-benzoxazine-6-carboxylic acid), a recently introduced second-generation fluoroquinolone, possesses excellent activity against Gram-positive, Gram-negative and anaerobic bacteria (Davis and Bryson, 1994; North et al., 1998). Compared to other fluoroquinolones, ofloxacin and ciprofloxacin, it also has more pronounced bactericidal activity against organisms such as Pseudomonas, Enterobacteriaceae and Klebsiella (Klesel et al., 1995). In human clinical trials, levofloxacin has been found very effective in the treatment of infections of the upper and lower respiratory tract, the genitourinary system, the skin and soft tissue (Davis and Bryson, 1994). Several species of staphylococci, streptococci including Streptococcus pneumoniae, most enterococci, enterobacteriaceae, E. coli, klebsiella, proteus, pseudomonas, bacteroides, clostridium, haemophilus, moraxella, legionella, mycoplasma and chlamydia are susceptible to levofloxacin (Langtry and Lamb, 1998). Levofloxacin is 100% available after oral administration (Chien et al., 1997). The drug distributes well to target body tissues and fluids in the respiratory tract, skin, urine and prostrate and its uptake by cells makes it suitable for use against intracellular pathogens (Langtry and Lamb, 1998). However, it penetrates poorly into the CNS. Levofloxacin is metabolized in the liver to demethyl-levofloxacin and levofloxacin N-oxide. About 80% of a dose is found in the urine as unchanged drug and ≤5% as inactive metabolites (Langtry and Lamb, 1998). The pharmacokinetics of levofloxacin has been investigated in humans (Verho et al., 1996; Amsden et al., 1999; Chulavatnatol et al., 1999; Gascon et al., 2000), rabbits (Mochizuki et al.,1994; Destache et al., 2001), rats (Ito et al., 1999) and guinea pigs (Edelstein et al., 1996). However, there is no information available on the pharmacokinetics of levofloxacin in cattle. In view of the marked species variation in the kinetic data of antimicrobial drugs,