Intraocular diclofenac and flurbiprofen concentrations in human aqueous humor following topical application

Flurbiprofen Na and diclofenac Na, two ocular antiinflammatory agents, were investigated to determine the aqueous humor concentrations in the human eye following topical application. One hundred sixty-five patients undergoing cataract surgery received a single drop of either diclofenac Na or flurbiprofen Na at selected times prior to the surgical procedure. Aqueous humor samples were aspirated at the beginning of surgery and a sensitive high-performance liquid chromatographic assay was used to determine the concentration of the antiinflammatory agent in the ocular fluid. Samples were obtained between 10 min and 24 hrs after a single instillation of the drug onto the cornea. The highest average concentration of diclofenac was 82 ng/ml at 2.4 hrs after instillation; concentrations remained above 20 ng/ml for over 4 hrs. Thereafter, between 3 and 16 ng/ml diclofenac could be assayed through 24 hrs. The highest average concentration of flurbiprofen, 60 ng/ml, was found at 2.0 hrs. The last detectable flurbiprofen concentration was measured at 7.25 hrs after instillation.