There are many reasons for the bitter mouth of a cold, such as fever, decreased function of the digestive tract, and medication factors. 1. Fever: Colds are caused by pathogens attacking the body, leading to an inflammatory response and fever. Abnormalities in the function of taste buds may occur during fever, which may lead to a bitter taste in the mouth. 2. Decrease in digestive function: The gastrointestinal function of the body decreases after a cold, and the liver and gallbladder function will also be affected, so there will be bitter mouth, loss of appetite, stomach distension and other phenomena. 3. Drugs: If you take drugs after a cold, most of them are bitter and can cause a bitter mouth. There are many reasons for bitter mouth, may also be caused by other diseases, such as symptoms continue to improve, it is recommended to go to the hospital in a timely manner to improve the examination, follow the doctor’s instructions to take standardized treatment, so as not to cause adverse consequences.