Strictly speaking, before the physical examination is not to drink water, if you need to take medicine or thirsty more, you can drink a small amount of plain water, but preferably not more than 200ml. drinking water is best about an hour before the physical examination, so that the water in the stomach when the physical examination is basically emptying, will not affect the examination. But before the physical examination must not drink too much water, not to mention sugary drinks, and can not and tea and coffee, otherwise it will affect the results of the physical examination. In the abdominal ultrasound examination is best not to drink water, if drinking water will also affect the results of the examination, but the bladder ultrasound requires holding urine, these examinations before the doctor will tell to drink more water to hold urine to check more clearly.