Stability of alprazolam, chloroquine phosphate, cisapride, enalapril maleate, and hydralazine hydrochloride in extemporaneously compounded oral liquids

Am J Health Syst Pharm. 1998 Sep 15;55(18):1915-20. doi: 10.1093/ajhp/55.18.1915.


The stability of five drugs commonly prescribed for use in oral liquid dosage forms but not commercially available as such was studied. Alprazolam 1 mg/mL, chloroquine phosphate 15 mg/mL, cisapride 1 mg/mL, enalapril maleate 1 mg/mL, and hydralazine hydrochloride 4 mg/mL were each 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, and cherry syrup and placed in 120-mL amber clear polyethylene terephthalate bottles. Three bottles of each liquid were stored at 5 degrees C and three at 25 degrees C, all in the dark. Samples were taken initially and at various times up to 60 days for analysis by high-performance liquid chromatography and assessment of appearance and odor; pH was measured. A mean of at least 91% of the initial drug concentration was retained for 60 days in the alprazolam, chloroquine phosphate, cisapride, and enalapril maleate liquids. The hydralazine hydrochloride liquids retained more than 90% of the initial concentration for only one day at 5 degrees C when prepared with Ora-Sweet-Ora-Plus and two days when prepared with Ora-Sweet SF-Ora-Plus and for less than a day in these preparations at 25 degrees C and in cherry syrup at 5 and 25 degrees C. No substantial changes in the appearance, odor, or pH of any liquid were observed. Alprazolam 1 mg/mL, chloroquine phosphate 15 mg/mL, cisapride 1 mg/mL, and enalapril maleate 1 mg/mL were stable in three extemporaneously compounded oral liquids for 60 days at 5 and 25 degrees C; hydralazine hydrochloride 4 mg/mL was stable at 5 degrees C for one day in Ora-Sweet-Ora Plus and for two days in Ora-Sweet SF-Ora-Plus.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alprazolam / analysis*
  • Chloroquine / analysis*
  • Chromatography, High Pressure Liquid
  • Cisapride / analysis*
  • Drug Compounding
  • Drug Stability
  • Enalapril / analysis*
  • Hydralazine / analysis*
  • Pharmaceutical Solutions


  • Pharmaceutical Solutions
  • Hydralazine
  • Enalapril
  • Chloroquine
  • Cisapride
  • Alprazolam