It can be caused by chronic lung disease that has been prolonged for a long time, or it can be caused by common allergies, or by cold and dampness in the lung meridians, resulting in poor circulation of the meridians. There are many allergic patients, because in Chinese medicine, this kind of patient is called persistent phlegm in the lung, that is, there is a root cause of the disease, the root of the disease is not in the lung, but in the lung meridians, so patients with allergies or asthma often feel uncomfortable in the back, some are feeling heavy, some are feeling like carrying a piece of ice in the back, this situation is actually a problem in the circulation of the lung meridians. The treatment for this is to activate the blood in the meridians, to remove as much phlegm as possible, and to clear out part of it, so that allergies or asthma will be less likely to attack.