Topical levofloxacin reduces ocular surface bacteria after 1 day

One-day and 3-day applications of topical levofloxacin show similar efficacy for reducing ocular surface bacteria, a study by researchers in California found. Applying povidone-iodine after levofloxacin further eliminated conjunctival bacteria, the study authors noted.

Christopher Ta, MD, and colleagues at Stanford University reviewed outcomes for 100 volunteer patients divided into two groups of 50 patients treated with topical 0.5% levofloxacin for ocular surface bacteria for either 1 day or 3 days.

"All patients received topical levofloxacin at 5-minute intervals for three applications, followed by two drops of topical 5% povidone-iodine," the authors said.

The researchers obtained conjunctival cultures before and after applying levofloxacin, as well as before and after povidone-iodine application, according to the study.

The number of eyes with positive conjunctival cultures significantly decreased from 41 eyes (82%) at baseline to 23 eyes (46%) in the 1-day treatment group (P = .0004).

The number of culture-positive eyes also significantly decreased among patients in the 3-day treatment group, from 37 eyes (74%) at baseline to 17 eyes (34%) at follow-up, (P = .0001), the authors reported.

There were no significant differences in rates of positive cultures between the two groups at any follow-up point, they noted.

"Two drops of povidone-iodine further reduced the positive culture rate for both groups to 20% (10 eyes for each group)," the authors said.

The study is published in the September-October issue of European Journal of Ophthalmology.