There are five major classes of anti-hypertensive drugs in common use, and if the drugs are selected reasonably, the blood pressure of most patients can be controlled within the ideal or normal range. A small number of hypertensive patients who take three or more anti-hypertensive drugs, including diuretics, and each drug is used in sufficient quantity and for sufficient time, but whose blood pressure is still 140/90 mmHg or above, are called recalcitrant hypertension, which is commonly known as difficult to control blood pressure. It is known that patients with hypertension are prone to heart enlargement, heart failure, arrhythmia, coronary heart disease, cerebrovascular disease, renal failure and a series of other diseases. And the higher the blood pressure, the greater the incidence and severity of these diseases; with blood pressure control, the incidence of these diseases will be greatly reduced, or even can be avoided. Obviously, patients with intractable hypertension, whose blood pressure is at a high level for a long time, will develop the above-mentioned diseases in a short period of time. Therefore, in the face of hypertensive patients whose blood pressure is difficult to control, it is important to go to the hospital in a timely manner to analyze and find the causes and further adjust the treatment. So, what are the factors that make it difficult to control blood pressure? According to our clinical experience, blood pressure is often difficult to control for the following reasons: 1, the concomitant conditions of hypertensive patients are not eliminated in a timely manner: such as the patient’s weight gain, excessive sodium intake, excessive alcohol consumption, the patient is in a highly stressed state, etc., their blood pressure is also difficult to control. 2, secondary hypertensive disorders are not treated for the cause: some secondary hypertensive disorders are not diagnosed in time due to atypical symptoms or unreasonable choice of examination and inaccurate judgment of results. Since they cannot be treated for the cause, of course, hypertension is difficult to control. In addition, in patients with secondary hypertension with a clear diagnosis, blood pressure is also difficult to control when the primary disease cannot be cured due to the specific lesion. Patients with hypertension who have difficulty controlling their blood pressure and their families are reminded to provide their doctors with a detailed medical history and to seek systematic consultation with a specialist who is engaged in clinical research on hypertension. 3, hypertension kidney damage on the treatment of hypertension: hypertensive patients are prone to kidney damage, which itself is the cause of hypertension. Therefore, hypertensive patients who are not treated in a timely and effective manner are prone to impaired kidney function, and then unreasonable use of diuretics, too much water and salt in the body can not be discharged out of the body, and even more hypertension, which makes it difficult to control blood pressure. 4, “white coat hypertension”: in the doctor’s clinic to measure blood pressure is always higher than normal, and even with several drugs are difficult to control to normal patients, while patients at home to measure their own blood pressure is normal, while checking the heart, brain, kidneys and other important organs without serious damage, the doctor called “white coat hypertension “White coat hypertension. 5, acute type of malignant hypertension: this is a special type of hypertension, its clinical characteristics are, blood pressure is significantly elevated, systolic and diastolic blood pressure can reach 200/130 mmHg or more, and continue to rise; symptoms are many and obvious, such as severe headache, vomiting, blurred vision, breathing difficulties; within a short period of time can appear heart, brain, kidney and other important organs of serious damage. The key to diagnosing this type of hypertension is that patients must be seen in a timely manner and hospitalized to receive systematic treatment to protect the heart, brain, and kidneys. 6, inappropriate anti-hypertensive treatment: if there are patients with hypertension, due to unreasonable treatment, there will also be unsatisfactory blood pressure control. These unreasonable manifestations are: ① The patient does not adhere to the medication. ②The drug dose is too small or the interval time is too long and the therapeutic effect is not achieved. ③Irrational drug selection or inappropriate combination of drugs. In fact, those whose blood pressure is not satisfactorily controlled due to improper treatment do not fall into the category of intractable hypertension.