Betalactam is a beta-blocker and is used clinically to treat hypertension and slow down the heart rate of patients. Routine administration of betalactam is not recommended for physical examinations and may lead to low blood pressure or slow heart rate in patients. Some patients may belong to the white coat hypertension, or see the staff in white clothes easily nervous, heart rate is accelerated, but the ECG above the heart rate is not qualified, this situation suggests that patients can take Betalac half an hour in advance, to buy flat tablets, such as 25mg, 50mg such dose is flat tablets, the onset of action will be faster. If the patient is worried about the slow onset of action, you can also chew, chew can basically take effect immediately, must pay attention to, if you usually have low blood pressure, do not eat this drug, so as not to make the blood pressure drop too low.