Whether or not you can take Si Wu Tang during menstruation needs to be judged according to your personal situation. If the menstrual period is light in color, it can be taken; if the menstrual period is dark in color and has blood clots, it is not recommended to take it. Four Substances Soup is mainly composed of four medicines: Angelica sinensis, Radix Rehmanniae Praeparata, Rhizoma Ligustici Chuanxiong and Radix Paeoniae Alba. It can be used to tonify and invigorate blood. It can be used to treat symptoms such as irregular menstruation, palpitations (rapid heartbeat, often accompanied by panic), insomnia, dizziness, colorless face, and pale tongue. Adverse effects have not been clarified and it is not recommended for those who are allergic to the ingredients of this medicine. Four Substances Tang is a blood tonic and can be taken if there are symptoms of blood deficiency during menstruation such as pale menstruation and low menstrual flow. It is not recommended to take it if there are no symptoms of blood deficiency. The use of the drug needs to be under the guidance of a physician, and it is recommended to go to the hospital in a timely manner.