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