The stability of sumatriptan succinate in extemporaneously prepared oral liquids

The stability of sumatriptan succinate in extemporaneously prepared oral liquids was studied. Suspensions of sumatriptan (as the succinate salt) in Ora-Sweet, Ora-Sweet SF, and Syrpalta syrups (Paddock Laboratories and Humco Laboratory) were extemporaneously compounded to produce a sumatriptan concentration of 5 mg/mL. Each suspension was prepared in triplicate. The suspensions were stored at 4 degrees C in amber glass bottles for 60 days. Two 1-mL samples were removed from each bottle initially and on days 2, 7, 14, 21, 28, 35, and 60. Sumatriptan concentrations were determined by high-performance liquid chromatography. The samples also underwent visual inspection and microbial testing. The mean concentration of sumatriptan in all suspensions remained above 90% of the initial concentration for up to 21 days. By day 28, the sumatriptan concentration of all suspensions had decreased to less than 90% of the initial concentration. None of the suspensions had microbial growth up to day 28, and there were no visible changes in the suspensions throughout the study period. Sumatriptan 5 mg/mL (as the succinate salt) in three oral suspensions was stable for up to 21 days when stored without light at 4 degrees C.