Methadone Hydrochloride USP POWDER FOR

Methadone, traditionally use in the treatment of heroin addiction, recently has been use to treat severe pain. The chemical stability of methadone has been studies in concentrations up to 1.5 mg/mL only. Commercial methadone concentrate (10mg/mL) and methadone powder was dilute to 5 mg/mL with orange-flavors Tang drink. Sodium benzoate was add to the solutions prepare from powder. Bottles were store at either room temperature (22 deg C) or under refrigeration (6 deg C) for 91 days. Samples were analyze in duplicate by a stability-indicating high-performance liquid chromatographic assay, and clarity and pH were also monitor. One additional solution was prepare from powder but no preservative was add; this solution was monitor for presence of bacterial growth at room temperature only. Solutions prepare from the concentrate and powder with preservative show no signs of change in clarity on storage. The solution made from powder only develop turbidity after 21 days, which suggest bacterial growth. There was no significant change in pH over the course of the study. After 91 days of storage at either room temperature or under refrigeration, there was no change in concentration for solutions prepare from concentrate or powder with preservative. Methadone solutions prepare from the commercial concentrate or powder with sodium benzoate are stable for 91 days at room temperature or under refrigeration. Solutions prepare from the powder but not containing a preservative show signs of bacterial growth after 21 days at room temperature. Methadone Hydrochloride USP POWDER FOR