Colds can sometimes lead to changes in taste, such as dry mouth and bitterness. Dry mouth means insufficient fluid in the mouth; bitter mouth means that there is fire and heat evil in the body. This time can be treated with Xiao Chai Hu Tang, because when dry mouth and bitter mouth is a deficiency of fluid and internal heat, it belongs to the evidence of Xiao Chai Hu Tang, which can be treated by taking Xiao Chai Hu granules or by applying Xiao Chai Hu Tang by prescribing prescriptions. In addition, even without treatment, if the cold passes its natural course, the symptoms of dry mouth and bitter mouth can be reduced or disappear. If it still does not reduce or disappear, you can choose the appropriate formula according to the clinical evidence to improve the symptoms of dry mouth and bitterness, and Xiao Chai Hu Tang can be applied at this time, with possible addition or subtraction based on this.