Xinran is the trade name of nifedipine controlled-release tablets, nifedipine controlled-release tablets are administered orally, 30 to 60 mg once a day. When the patient has serious cerebrovascular disease or hepatic impairment, the dosage should be appropriately reduced. Nifedipine is a dihydropyridine calcium channel blocker, which can block the calcium channels of cardiac muscle, vascular smooth muscle and other cells, thus reducing intracellular calcium ions and inhibiting the contraction of cardiac muscle and vascular smooth muscle. Clinically, it is mainly used in the treatment of hypertension and angina pectoris. The main adverse effects of nifedipine are hypotension, palpitations (rapid heartbeat, often accompanied by panic), peripheral edema, myocardial infarction, ventricular arrhythmia, facial flushing, nausea, abdominal distension, diarrhea, constipation, dizziness, headache and so on. Nifedipine is contraindicated in people who are allergic to the components of the drug, in patients with cardiogenic shock, in pregnancy up to 20 weeks, as well as in breastfeeding women. It should be noted that nifedipine controlled-release tablets can not be broken or chewed and taken, because it will destroy its structure, which will lose the effect of controlled release, and will cause excessive absorption of the drug at one time, causing low blood pressure. Nifedipine controlled-release tablets, when used in the treatment of hypertension, must be used under the guidance of a specialist physician, according to the blood pressure level of timely adjustment of the dose, while monitoring the adverse effects, if any discomfort in a timely manner to consult the doctor.