Aqueous humour levels of topically applied ciprofloxacin and ofloxacin in the same subjects

Purpose To evaluate aqueous humour levels of: topical 0.3% ciprofloxacin an d 0.3% ofloxacin in the same subjects, Methods Thirty-two bilateral cataractous patients received topical 0.3% cip rofloxacin in one eye and 0.3% ofloxacin in the other eye before each catar act extraction, Eyedrops were repetitively instilled for 6 h. Aqueous humou r samples were collected and assayed for drug concentrations by a method de scribed originally by us using high-performance liquid chromatography. Results Mean aqueous ciprofloxacin and ofloxacin levels were 0.33 +/- 0.04 mu g/ml (mean +/- SEM) and 1.34 +/- 0.14 mu g/ml respectively (p<0.0001). Conclusion Ofloxacin level in the aqueous humour is 4 times higher than tha t of ciprofloxacin in the same subjects.