Drinking water two hours before doing biochemistry will not have much effect, the amount of water consumed is not more than 100 ml, which generally will not affect the correctness of the test results. Biochemical tests include liver function tests, kidney function tests, lipid tests, blood sugar tests, etc. These tests require absolute fasting, meaning that no food is allowed after 10 p.m. on the night before the test, and the fasting period is 8 to 10 hours. Fasting time is recommended to prohibit eating, but you can drink a small amount of water, the amount of water does not exceed 100 ml, the morning of the blood test, the patient if there is high blood pressure, high blood sugar and other chronic cardiovascular diseases, you can drink appropriate boiled water orally medication, to avoid the inspection period lead to the patient’s blood pressure, blood glucose sharp rise in the problem. Regarding the relevant preparation before the test biochemistry, it is recommended that you can consult the internal medicine doctor or laboratory doctor in regular hospitals.