The efficacy of 0.5% proparacaine stored at room temperature

Objective To evaluate the efficacy of 0.5% proparacaine stored at room temp erature for 6 weeks. Animals studied Six normal dogs, evaluated on a weekly basis for 6 weeks. Procedure Proparacaine stored at 4 degreesC or at room temperature, was eva luated in the right and left eye of each dog, respectively. Corneal sensiti vity was assessed with a Cochet-Bonnet aesthesiometer before and after inst illation of proparacaine at each time point. Results A statistically significant difference was seen in corneal sensitiv ity beginning at week 3 for the eyes receiving room-temperature proparacain e compared to refrigerated proparacaine. Differences were not seen between right and left eyes before instillation of proparacaine for any time point, nor for eyes receiving refrigerated proparacaine over the 6 week study per iod. Conclusion Short-term storage of proparacaine at room temperature did not a ffect efficacy, but storage at room temperature for more than 2 weeks resul ted in a decrease in drug effect.