Enrofloxacin-associated ocular disease in cats: A scoping review

Ocular effects, most notably retinal degeneration, have been linked to enrofloxacin use in cats. However, data have been limited and there is a need for formal evidence synthesis to better understand and characterize these potentially life-altering adverse events.

The objective was to describe data regarding ocular adverse events associated with enrofloxacin administration in cats and to identify information gaps.

A scoping review was conducted, searching the MEDLINE (via the Ovid platform), Web of Science, and CAB Abstracts bibliographic databases.

Six references passed title and abstract screening, then full text screening: 1 case series (n = 17 cases), 3 single case reports, 1 conference research abstract (n = 2 cases), and 1 pharmacovigilance summary publication. There were reports of enrofloxacin-associated adverse ocular events in 163 cats. Loss of vision, mydriasis, and altered pupillary light responses were most commonly reported. Increased tapetal reflectivity, retinal vessel attenuation, and retinal degeneration were the most common abnormalities on ophthalmological examination. Most cats had permanent blindness or altered vision. Most cats had received doses well in excess of the current label recommendation, but 15/103 (14%) cats for which dosing data were available were reported to have received ≤ 5 mg/kg per day.

Suspected enrofloxacin-associated ocular disease in cats typically resulted in long-term blindness or visual deficits, but full recovery occurred in a subset. Inadequate data were available to assess potential risk factors (e.g., age, dose). Although a dose of ≤ 5 mg/kg per day will likely reduce the likelihood of adverse events, these data indicated that ocular disease was still possible at that dosage.