Fill levels, cost comparisons, and expulsion force requirements of commonly used topical ophthalmic nonsteroidal anti-inflammatory drugs

Abstract

Purpose: To determine volume fill levels, estimated costs, and force expulsion requirements per bottle of topical ophthalmic nonsteroidal anti-inflammatory drugs (NSAIDs) commonly perioperatively in the United States. Setting: Tertiary care academic medical center. Design: Prospective laboratory investigation. Methods: 8 commercially available NSAIDs (3 branded, 5 generic) were tested: branded bromfenac 0.07%, generic bromfenac 0.09%, diclofenac 0.1%, flurbiprofen 0.03%, generic ketorolac 0.5%, branded ketorolac 0.5%, ketorolac 0.47%, and branded nepafenac 0.3%. 10 bottles of each medication were tested, with an additional bottle tested for expulsion force requirements. A double-blinded method was used to measure the actual bottle fill volume and number of drops per bottle. The total cost per drop was calculated using published cash prices. Force requirements were measured using a customized force gauge apparatus. Formulations were compared using the Kruskal-Wallis test, followed by pairwise comparisons with the Dwass, Steel, Critchlow-Fligner Method. Results: 2 branded NSAIDs (bromfenac and nepafenac) had slightly lower-than-sticker volumes while generics other than ketorolac had higher-than-sticker volumes. Diclofenac and branded bromfenac had the highest and lowest adjusted number of drops respectively. Generic bromfenac and generic ketorolac had the highest and lowest adjusted volume compared with sticker volume respectively. Branded bromfenac was the most expensive medication, while generic diclofenac was the least expensive. Force expulsion requirements varied significantly among generic and branded NSAIDs. Conclusions: Volume fill levels, patient-incurred costs, and expulsion force requirements per bottle of topical NSAID medications vary significantly. Surgeons may wish to consider these factors when deciding how best to use these medications perioperatively.