Stability of tacrolimus in an extemporaneously compounded oral liquid

The stability of tacrolimus in an extemporaneously compounded oral liquid formulation was studied. A suspension was prepared by mixing the contents of commercially available 5-mg capsules of tacrolimus with equal amounts of Ora-Plus and Simple Syrup, NF, to make a final volume of 60 mL. The final concentration of tacrolimus in the suspension was 0.5 mg/mL. Six identical suspensions were prepared, placed in three glass and three plastic amber prescription bottles, and stored at room temperature (24-26 degrees C). Immediately after preparation and at 7, 15, 30, 45, and 56 days, samples were removed and assayed in duplicate by stability-indicating high-performance liquid chromatography. At least 98% of the initial tacrolimus concentrations remained in all suspensions throughout the study period. Color, order, and pH did not change appreciably over the study period. Tacrolimus 0.5 mg/mL compounded extemporaneously in equal amounts of Ora-Plus and Simple Syrup, NF, was stable at 24-26 degrees C for at least 56 days in both glass and plastic amber prescription bottles.