Always have no energy is non-specific, many diseases can be manifested as peripheral weakness. Endocrine common causes: First, check the blood sugar, if the patient has severe hyperglycemia, the body’s energy supply is insufficient, there can be fatigue, but may also be combined with dry mouth, drinking, urination and weight loss and other symptoms. Second, the more common endocrine diseases such as hyperthyroidism or hypothyroidism, can also be manifested as fatigue, need to improve the thyroid function, thyroid ultrasound and other tests to clarify. Third, if there are electrolyte disorders, such as combined with hyponatremia, hypokalemia, etc., can also appear weakness, need to improve the electrolyte examination to clarify.