Stability of granisetron hydrochloride in an extemporaneously prepared oral liquid

The stability of granisetron 0.2 mg/mL (as the hydrochloride salt) in an extemporaneously prepared oral liquid was studied. Twelve 1-mg granisetron tablets were pulverized and suspended in 30 mL of distilled water. This mixture was then diluted with cherry syrup to produce a 60-mL oral liquid with a granisetron concentration of 0.2 mg/mL. Half of the preparation was stored at 5 degrees C, and half was stored at 24 degrees C. Samples were taken on days 0, 1, 2, 3, 4, 6, 8, 10, 12, and 14 and assayed by high-performance liquid chromatography. There was no change in the liquid's color, consistency, or pH, and the concentrations of granisetron ranged from 97% to 104% of initial concentration during the 14 days at 5 and 24 degrees C. Granisetron 0.2 mg/mL (as the hydrochloride salt) in an extemporaneously prepared oral liquid was stable for up to 14 days.