The visual and chemical compatibility of propranolol hydrochloride injection admixtures in large-volume parenteral solutions (LVPs) packaged in plastic containers was studied. Propranolol hydrochloride injection was mixed with five different LVPs manufactured by three suppliers and packaged in plastic containers. Two concentrations (0.5 and 20 micrograms/ml) were tested. Samples were obtained via administration sets with 0.2-micron final filters. Visual appearance, pH, and propranolol hydrochloride concentration (HPLC method) of the admixtures were evaluated at 0, 4, 8, and 24 hours after preparation at room temperature and with ambient lighting. No change in visual appearance was observed. The pH of the admixtures ranged from 3.9 to 6.4, depending on the composition of the intravenous infusion fluid and propranolol hydrochloride concentration. There was no significant loss in potency during the test period. Additionally, there was no adsorption of propranolol hydrochloride onto the surface of polyvinyl chloride bags or polyolefin containers, or onto the filters. Propranolol hydrochloride can be mixed with common intravenous infusion fluids for 24 hours without compatibility problems when administered under normal conditions.