The nanometer emulsion oral liquid of andrographolide consists of surfactant, oil, andrographolide and distilled water. Its preparation process includes the following steps:weighing surfactant with or without co-surfactant; calculating HLB value and selecting oil for reaching emulsifying HLB value near that of the surfactant phase; changing the ratio between the surfactant phase and the oil phase regularly to dissolve andrographolide in the surfactant; adding distilled water slowly at 20-25 deg.c to form clear and flowing O/W type stable nanometer emulsion oral liquid. The nanometer emulsion oral liquid has high dissolubility of andrographolide, raised bioavailability of andrographolide, less stimulation to gastrointestinal tract and raised patient's compliance, and may be also taken easily by children and persons with dysphagia. |