Usually if your blood pressure is too low after taking nifedipine extended-release tablets, you can choose to change to valsartan, irbesartan and other antihypertensive drugs. The main reason is that nifedipine extended-release tablets work gradually in the body and lower blood pressure for a longer period of time. But valsartan and irbesartan antihypertensive drugs, the time to reduce blood pressure will be shorter, not to the situation of blood pressure reduction is too serious. But a small number of people, there are double renal artery stenosis or hyperkalemia and other conditions, belonging to the contraindication group of valsartan, irbesartan drugs, then can not be taken. In addition, there are some common adverse reactions to valsartan and irbesartan, such as dizziness, nausea and fatigue. The application of antihypertensive drugs should be carried out under the guidance of a professional doctor, do not use on your own, or increase or decrease the dose at will.