Purpose: The aim of this study was to compare the anti-inflammatory activities of ketorolac
tromethamine 0.4% and 0.1%; diclofenac sodium 0.1%; and loteprednol etabonate 0.5%
suspension in an animal model of ocular inflammation.
Methods: An ocular inflammatory response was induced in New Zealand White rabbits by
the intravenous (i.v.) administration of 10 µg/kg lipopolysaccharide (LPS). In study animals,
1 eye was treated topically with 50 µL of study medication (n = 8 animals per drug) and the
other eye was treated topically with a 50-µL vehicle (buffered saline). In control animals (n =
8), both eyes were treated with vehicle. All animals were treated twice: 2 h and 1 h before
LPS challenge. The breakdown of the blood-aqueous barrier in the anterior chamber was measured
by fluorophotometry (FITC-dextran 30 mg/kg, i.v. given immediately after LPS challenge).
Aqueous prostaglandin E2 (PGE2) levels were measured using an enzyme-linked immunosorbent
assay (ELISA) immunoassay.
Results: Ketorolac 0.4% resulted in a nearly complete inhibition of endotoxin-induced increases
in FITC-dextran and PGE2 synthesis (P < 0.001 vs. vehicle). Diclofenac 0.1% had much
less of an effect on these parameters (P < 0.01 vs. ketorolac 0.4%). Loteprednol 0.5% was no
more effective than vehicle at inhibiting increases in FITC-dextran.
Conclusions: Ketorolac has greater anti-inflammatory effects than diclofenac and loteprednol.
