Abstract
In order to monitor the plasma theophylline level in asthmatic patients given aminophylline intravenously, the efficiency of high-pressure liquid chromatography in measuring the blood level was examined. This method requires only 200μl of serum or plasma sample. It also produces satisfactory results in view of the lineality of the standard curve, precision and analytical recovery within a therapeutic level. In the clinical application, an ampule of Neophyllin (Eisai) was injected into an asthmatic patient intravenously. The blood level of theophylline was about 15.6μg/ml immediately after the injection and decreased to a half level after one hour. The half-life thereafter was about 8 hours.
