If a patient experiences shivering, panic and chills, it may be due to the presence of hypothyroidism or because the patient is currently in a febrile phase, such a patient may experience this abnormal manifestation. During the onset of discomfort, the patient can first take the temperature, do an electrocardiogram, measure the heart rate and blood pressure, and check cardiac enzymes, blood count, and thyroid function if necessary to help further clarify the diagnosis. If the patient has shivering, panic attacks, and chills with bradycardia, and is often weak and constipated on weekdays, it is highly considered to be due to hypothyroidism. If the patient is currently accompanied by fever, cough and sputum, it is likely to be due to a lung infection, or a respiratory tract infection. Lung CT, cardiac ultrasound and ambulatory electrocardiogram can be done if necessary.