Drugs that activate blood circulation and eliminate blood stasis (promoting blood circulation and eliminating blood stasis in the body) may lengthen the menstrual period and are not recommended for treatment if there is not an evidence of blood stasis and obstruction. Common medicines used in Chinese medicine to activate blood circulation and remove blood stasis include Chuanxiong, Yanhusuo, Uljin, Turmeric, Boswellia, etc. These medicines are mainly used for various diseases with blood stasis obstruction, such as headache, chest pain, abdominal and heart pain, dysmenorrhea, postpartum abdominal pain, paralyzing pain in limbs, and stagnant pain in bruises and injuries. In the case of irregular menstruation, mainly due to stagnation of blood stasis and obstruction of menstruation, such as low menstrual flow, dark color, delayed menstruation, etc., it can be treated with medicines that invigorate blood circulation and eliminate blood stasis. However, they are generally not recommended for use during menstruation and may lead to prolonged periods. The use of such drugs may also lead to prolonged periods in those who do not have blood stasis and obstruction. Patients are advised to consult a doctor if they are not feeling well, and are advised to consult a doctor for specific medication.