The stability of 10mg/mL zidovudine and either 12.5mg/mL dobutamine or 25 mg/L ranitidine hydrochloride stored in 0.9% sodium chloride and 5 % dextrose injections in 50 cc polyvinyl chloride (PVC) bags stored at 4 degrees Celsius and ambient temperature up to 24 hr was studied. Samples were analysed at 0, 4, 8, and 24 hr after preparing the controls and known mixtures, using a reversed phase stability indicating HPLC assay. The drug mixtures were stable up to 24 hrs as shown by the % remaining drug concentrations above 90 % at the respective sampling times.The pH of the drug solutions remained constant over time. These data support unequivocally the stability of zidovudine/dobutamine or zidovudine/ranitidine admixtures under the storage conditions studied in this investigation.