Stability of acetazolamide, allopurinol, azathioprine, clonazepam, and flucytosine 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. Acetazolamide 25 mg/mL, allopurinol 20 mg/mL, azathioprine 50 mg/mL, clonazepam 0.1 mg/mL, and flucytosine 10 mg/mL were prepared in 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 polyethylene terephthalate bottles. The sources of the drugs were capsules and 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 initially and at intervals up to 60 days and analyzed for drug concentration by stability-indicating high-performance liquid chromatography. At least 94% of the initial drug concentration was retained in all the oral liquids for up to 60 days. There were no substantial changes in the appearance or odor of the liquids, or in the pH. Acetazolamide 25 mg/mL, allopurinol 20 mg/mL, azathioprine 50 mg/mL, clonazepam 0.1 mg/mL, and flucytosine 10 mg/mL were stable for up to 60 days at 5 and 25 degrees C in three extemporaneously compounded oral liquids.
Allen
L V
LV
College of Pharmacy, University of Oklahoma Health Sciences Center, Oklahoma City 73117, USA. loyd-allen@uokhsc.edu
Erickson
M A
MA
D000086:Acetazolamide / Q000032:analysis*; D000493:Allopurinol / Q000032:analysis*; D001379:Azathioprine / Q000032:analysis*; D002626:Chemistry, Pharmaceutical; D002851:Chromatography, High Pressure Liquid; D002998:Clonazepam / Q000032:analysis*; D004338:Drug Combinations; D004339:Drug Compounding; D004344:Drug Incompatibility; D004355:Drug Stability; D005437:Flucytosine / Q000032:analysis*; D006863:Hydrogen-Ion Concentration; D012996:Solutions; D013696:Temperature
D004338:Drug Combinations; D012996:Solutions; D002998:Clonazepam; D000493:Allopurinol; D005437:Flucytosine; D001379:Azathioprine; D000086:Acetazolamide