速效伤风胶囊是治疗感冒的常规药物，主要成分为对乙酸氨基酚。浙江、河北两省药品标准均收载外指示剂法测定乙酸氨基酚。笔者试用复合型内指示剂法，终点明显。现报道如下。1方法与结果按上述省药品标准操作，唯在滴定前在试样中加入0．1％橙黄IV指示液4～5滴，015％亚甲蓝指 Quick-acting cold capsule is a common drug for the treatment of common cold, the main component of acetaminophen. Zhejiang, Hebei Province, two provinces drug standards are included in the external indicator determination of acetaminophen. The author tried composite type indicator method, the end point is obvious. Report as follows now. 1 Methods and Results According to the provincial pharmaceutical standards operation, only before the titration in the sample by adding 0.1% of the yellow IV indicator solution 4 to 5 drops, 015% methylene blue means