将生石膏单方及两种复方，经回流煎煮，每隔１０ｍｉｎ取样１ｍｌ，采用ＣＸ３型ＢＥＣＫＭＡＮ生化自动分析仪，以偶氮胂Ⅲ法测定钙含量。实验结果表明，以钙的煎出量为指标，生石膏入煎剂不需先煎久煎，而生石膏入煎剂需先煎久煎源于《伤寒论》可能为误传 The raw gypsum single and two compounds were decocted by reflux, and 1 ml was sampled every 10 minutes. The CX3 type BECKMAN biochemical analyzer was used to determine the calcium content by the azo III method. The experimental results show that, with the amount of calcium decocted as an indicator, raw gypsum can be decocted without decocting for a long time, while raw gypsum can be decocted into decoction for a long time.