Stability of baclofen, captopril, diltiazem hydrochloride, dipyridamole, and flecainide acetate in extemporaneously compounded oral liquids.

The stability of drugs commonly prescribed for use in oral liquid dosage forms but not commercially available as such was studied. Baclofen 10 mg/mL, captopril 0.75 mg/mL, diltiazem hydrochloride 12 mg/mL, dipyridamole 10 mg/mL, and flecainide acetate 20 mg/mL were prepared in a 1:1 mixture of Ora-Sweet and Ora-Plus (Paddock Laboratories), a 1:1 mixture of Ora-Sweet SF and Ora-Plus (Paddock Laboratories), and cherry syrup and placed in 120-mL amber, clear polyethylene terephthalate bottles. The source of all the drugs was tablets. Six bottles were prepared per liquid; three were stored at 5 degrees C and three at 25 degrees C, all in the dark. A sample was removed from each bottle immediately after preparation and at various intervals up to 60 days and analyzed for drug concentration by stability-indicating high-performance liquid chromatography. A mean of at least 92% of the initial drug concentration was retained for up to 60 days in the baclofen, diltiazem hydrochloride, dipyridamole, and flecainide acetate liquids at both 5 and 25 degrees C. There were no substantial changes in the appearance or odor of any of the liquids or in the pH. Baclofen 10 mg/mL, diltiazem hydrochloride 12 mg/mL, dipyridamole 10 mg/mL, and flecainide acetate 20 mg/mL were stable for up to 60 days at 5 and 25 degrees C in three extemporaneously compounded oral liquids.