There are many herbal formulas for asthma, the main representative ones can be chosen to dispel wind and cold, promote the lung and calm asthma, such as Ma Huang Tang with reduction, the main ingredients of which are Ephedra, Gui Zhi, Roasted Licorice and Almond. In the formula, ephedra and cinnamon branch can promote the lung and calm asthma, dispel cold and relieve symptoms. Almonds can help ephedra to lower lung qi and calm asthma, and can dispel external evil. The roasted licorice can harmonize the herbs. The combination of the four herbs can dispel sweat and relieve symptoms, promote the lung and calm asthma. If cold phlegm obstructs the lung and phlegm is unfavorable, Er Chen Tang is added to resolve phlegm and relieve qi. If the cough and asthma is caused by branching drinks and external cold, with sputum being thin and clear, Xiao Qing Long Tang can be used to dispel the cold from the exterior and resolve the phlegm inside.