Aqueous and vitreous penetration of oral cefixime and ciprofloxacin in rabbit eye

ABSTRACT

To investigate the penetration of cefixime and ciprofloxacin to the rabbit eye on the basis of microbial inhibition of aqueous and vitreous humour after oral administration. In this experimental study, 36 rabbits [72 eyes] were randomly divided into two groups; group A consisted of 20 rabbits and group B 16 rabbits. Each group was divided into four equal subgroups. The rabbits in each subgroup of group A received 4, 8, 12, and 20 mg/kg of syrup of cefixime every 12 hr respectively and the rabbits in each subgroup of group B received 20, 40, 60, and 80 mg/kg tablet of ciprofloxacin respectively every 12 hr. Immediately after the first dose of the drugs, the anterior chamber of one eye was irrigated randomly by 30-40 cc of ringer lactate solution alongside with mild traumatization of iris. Then by 4, 8, 12, 24 and 72 hr intervals after the 3rd dose, 0.1 cc of aqueous, 0.2-0.5 cc of vitreous, 3 cc of blood and one standard disk of the used antibiotic was placed on culture media of a known bacteria which was completely sensitive to the respective antibiotic. Forty eight hours later, the microbial inhibition zone of each sample and the standard disk of antibiotic were compared. No microbial inhibition was seen by sample of aqueous and vitreous, although very large zone of inhibition was seen by blood sample and standard disk of antibiotic. It seems that oral cefixime and ciprofloxacin do not produce an effective dose for microbial inhibition in rabbit eye