If you feel weak and dizzy, there are usually four factors as follows: First, the most common factor is the initial stage of the cold, whether it is a bacterial cold, viral cold or atypical, pathogenic cold, there will be clinical symptoms of weakness, dizziness and dullness in the early stage of the cold, often due to the immunological effect of the virus being expelled from the body. Second, often due to ionic disorders in the body, usually hypokalemia and hyponatremia, there will be weakness, dizziness, dull head clinical symptoms. Third, the above clinical manifestations will also occur when the brain is acutely deprived of oxygen, such as insufficient oxygen supply to brain cells leading to low peripheral oxygen saturation and high partial pressure of carbon dioxide, which will lead to brain cell dysfunction due to lack of oxygen and will result in a dull head with no strength in the periphery. Fourthly, dizziness and headache with weakness of the periphery can also occur when cerebrovascular ischemia occurs.