The diagnosis of hypertension level 3 is mainly based on the blood pressure, and the diagnosis of hypertension level 3 can be made by measuring the blood pressure. There is also a situation where the high pressure is within the normal range or the high pressure does not reach 180mmHg, but the low pressure has exceeded 110mmHg, this also belongs to hypertension level 3, as long as the high pressure exceeds 180mmHg and the low pressure exceeds 110mmHg, it is diagnosed as hypertension level 3. Hypertension level 3 is the most serious level of hypertension, patients often have severe headaches, dizziness or panic attacks, hypertension level 3 requires a combination of two or more antihypertensive drugs, a single antihypertensive drug may not be able to reduce blood pressure within the normal range.