Feeling short of breath every morning around 4 am may be due to allergic asthma, myocarditis, left heart failure and other diseases. 1. Allergic asthma: allergic asthma may be genetic, dust mite, pet dander and other factors. Patients may experience shortness of breath, chest tightness, cough, coughing, dyspnea, etc. Some patients may feel short of breath around 4 am every morning. 2. Myocarditis: Myocarditis may be caused by infection, autoimmune factors, physical, chemical and other factors. Patients may have shortness of breath, palpitations, chest tightness, dizziness, dyspnea and other symptoms, and some patients may feel short of breath at around 4:00 am every day. 3. Left heart failure: Left heart failure may be caused by sepsis, anemia, pulmonary embolism, drugs, aortic insufficiency and other factors. Symptoms are dyspnea, telangiectasia, and fatigue, etc. Patients may feel short of breath during an acute attack around 4 am every morning. There are many reasons for feeling short of breath around 4 am every morning, and patients are advised to seek timely medical attention to identify the cause.