Benadryl hydrochloride is usually better to take before meals, some patients need to follow the doctor’s advice to adjust the time of taking. Because most of the hypertensive patients are in the eight to ten o’clock this range of blood pressure rise is more obvious, must take antihypertensive drugs as soon as possible, will maintain the effect of the drug in the eight to ten o’clock in this range, which is conducive to the stabilization of blood pressure, so most of the time for the Benadryl hydrochloride tablets are placed in the morning before the meal to take. If patients still have elevated blood pressure in the afternoon, it may be necessary to combine with the individual’s own blood pressure changes to adjust the time of taking the drug, such as follow the doctor’s instructions to adjust to take after meals or take in the afternoon. The common adverse effects of the drug are dry cough, angioneurotic edema and so on. Contraindications patients such as Benadryl allergy, history of angioneurotic edema, isolated kidneys, transplanted kidneys, bilateral renal artery stenosis and other contraindications to the use of the drug. It is recommended that patients follow the doctor’s instructions to take the drug on time, if there is a dry cough and other adverse reactions, you should consult a doctor in time to make adjustments to the drug.