Baijiahei, or Aminophenol Pseudomefenesin Tablets, is mainly used for the treatment and relief of symptoms such as fever and headache, peripheral aches and pains, sneezing, runny nose, nasal congestion, and cough caused by colds. This drug has certain characteristics that the drug has two different ingredients, which are divided into white and black tablets. The white tablet, also known as the day tablet, needs to be taken during the day and the other black tablet, known as the night tablet, needs to be used at night. The main ingredients of the daytime tablets include acetaminophen, pseudoephedrine hydrochloride and dextromethorphan hydrobromide, which have antipyretic, analgesic, anti-cough and anti-inflammatory effects, and can also constrict the capillaries of the upper respiratory tract, thus reducing symptoms such as nasal congestion, itchy eyes and congestion of the nasal mucosa. In addition to the above ingredients, the night tablet adds Benadryl hydrochloride, an antihistamine, which not only can further reduce the symptoms of nasal congestion, runny nose and sneezing during cold and flu, but also has a sedative and tranquilizing effect, which helps to sleep after taking. Therefore, both the white and black tablets have basically the same drug effect. However, in some cases, white tablets can also be taken at night, but avoid taking black tablets during the day, so that patients will not feel sleepy during the day, which is not conducive to normal life, study and work.