Shortness of breath and weakness can be seen in a number of systemic diseases, common respiratory diseases such as bronchial asthma, circulatory diseases such as congestive heart failure, neurological diseases such as cerebral infarction and metabolic diseases such as anemia. 1. Respiratory system diseases: such as bronchial asthma, emphysema, chronic obstructive pulmonary disease and other patients often appear shortness of breath, generalized weakness, often accompanied by cough and other symptoms, lung auscultation may appear abnormal breath sounds. 2. Circulatory system diseases: such as myocardial ischemia, congestive heart failure and other diseases, shortness of breath and weakness, often accompanied by chest tightness, panic, sitting breathing and other symptoms, electrocardiogram, cardiac ultrasound can assist in the diagnosis. 3. Neurological diseases: some neurological diseases can also cause asthenia, such as cerebral infarction patients, often accompanied by headache, limb movement or sensory impairment, cranial CT or nuclear magnetic can be clearly diagnosed. 4. Metabolic diseases: acute massive blood loss can lead to anemia, causing shortness of breath and weakness, often accompanied by increased heart rate, palpitations and so on. There may be other reasons for asthma weakness, it is recommended to go to the hospital in time, improve the examination to clarify the cause of the disease and standardize the treatment.