LORAZEPAM STABILITY IN PARENTERAL SOLUTIONS FOR CONTINUOUS INTRAVENOUS ADMINISTRATION

OBJECTIVE: To determine the stability of lorazepam over a 24-hour peri od when prepared in polyvinyl chloride (PVC) bags at initial concentra tions of 0.08 and 0.5 mg/mL. DESIGN: Each concentration was studied at room (21 degrees C) and refrigerator (4 degrees C) temperatures in de xtrose 5% (D5W) and NaCl 0.9% solutions. Duplicate test solution admix tures were prepared for each lorazepam concentration, diluent, and tem perature. At 0, 1, 4, 8, and 24 hours, duplicate samples were obtained for visual inspection, pH determination, and concentration determinat ion by stability-indicating, reverse-phase HPLC analysis. Compared wit h baseline, peaks for lorazepam degradation products were not found on any of the study chromatograms. RESULTS: In D5W and NaCl 0.9% solutio ns, lorazepam loss in excess of 10% by HPLC analysis occurred for conc entrations of 0.08 and 0.5 mg/mL at 1 and 4 hours, respectively. CONCL USIONS: These data suggest that significant loss of lorazepam occurs a s the probable result of sorption to PVC bags when admired in both D5W and NaCl 0.9% solutions at 21 and 4 degrees C.