Antihypertensive drugs taken in combination with hydrochlorothiazide can increase the antihypertensive effect of antihypertensive drugs, for the antihypertensive effect is more obvious. Hydrochlorothiazide belongs to the traditional diuretic, antihypertensive drugs, for a small dose of hydrochlorothiazide, can play a slight diuretic effect, and vasodilatory effect is more obvious, the effective rate of antihypertensive can reach more than 80%, better than all other antihypertensive drugs. It can reverse left ventricular hypertrophy while lowering blood pressure; it can be used alone or taken in combination with other antihypertensive drugs, and when used in combination, it can increase the blood pressure-lowering effect of other antihypertensive drugs and produce synergistic antihypertensive effect, which will significantly improve the effect of lowering blood pressure. The drug may cause dry mouth, irritable thirst, muscle cramps, nausea, vomiting, extreme fatigue and weakness, hyperglycemia, hyperuricemia during administration. Allergic reactions such as rash and hives. The drug is used with caution in pregnant women and is contraindicated in lactating women. Therefore, for the use of medication recommendations should be regulated in accordance with medical advice, do not self-medication.