The penetration of oral ciprofloxacin into the aqueous humor, vitreous, and subretinal fluid of humans.

We examined ciprofloxacin levels in the aqueous humor, vitreous, or subretinal fluid in 40 patients undergoing cataract extraction, vitrectomy, or scleral buckling. Ciprofloxacin, 750 mg, was administered orally an average of 17 1/2 and 5 1/2 hours preoperatively. We obtained mean ciprofloxacin levels of 0.53 microgram/ml in aqueous humor, 0.51 microgram/ml in vitreous, and 0.71 microgram/ml in subretinal fluid. These vitreous levels exceed the minimum inhibitory concentration (MIC)90 of Staphylococcus epidermidis, Propionibacterium species, Pseudomonas aeruginosa, Proteus mirabilis, and Haemophilus influenzae, as well as the MIC70 of S. aureus and Bacillus cereus. Therefore, ciprofloxacin may have a role in the management and prevention of endophthalmitis.