Fosphenytoin Y-site Stability Studies with Lorazepam and Midazolam Hydrochloride
Author(s): Riggs Robert M, English Brett A, Webster Andrew A, McGuire J Michael, Riordan James M, Worthington Mary A
Issue: May/Jun 1999 - Compounding for Animals
View All Articles in Issue
Page(s): 235-238
Download in electronic PDF format for $75
Abstract: The treatment of status epilepticus may require in certain situations the concurrent administration of lorazepam or midazolam with fosphenytoin. Simulated Y-site fosphenytoin/ lorazepam and fosphenytoin/midazolam hydrochloride admixtures, respectively, in 0.9% sodium chloride injection were analyzed using a stability-indicating high-performance liquid chromatography (HPLC) method. Each drug was analyzed for stability by HPLC from three simulated Y-site samples over an eight-hour period. The HPLC assay results indicate that both fosphenytoin and lorazepam are stable together at a Y site over an eight-hour period. In addition, there was neither a change in sample clarity nor a change in pH over the same period. The results indicate that, when medically necessary, fosphenytoin and lorazepam in 0.9% sodium chloride injection can be administered via the same intravenous (IV) line. Midazolam free base was precipitated upon admixture of midazolam hydrochloride and fosphenytoin solutions. Therefore, midazolam hydrochloride and fosphenytoin should not be given via the same IV line.