Blood Pressure Levels
Blood pressure levels is measurement of the force of blood against the walls of arteries. Blood pressure is recorded as two numbers-the systolic pressure (as the heart beats) over the diastolic pressure (as the heart relaxes between beats). The measurement is written one above or before the other, with the systolic number on top and the diastolic number on the bottom. For example, a blood pressure measurement of 120/80 mmHg (millimeters of mercury) is expressed verbally as "120 over 80." Normal blood pressure is less than 120 mmHg systolic and less than 80 mmHg diastolic - 160/80 mmHg would be stage 2 hypertension (high blood pressure).
Blood pressure is measured in millimeters of mercury (mm Hg). The classifications below are for people who are not taking blood pressure-lowering drugs (antihypertensive) and are not acutely ill. When a person's systolic and diastolic pressures fall into different categories, the higher category is used to classify the blood pressure status. Diagnosing high blood pressure is based on the average of two or more readings taken at each of two or more visits after an initial screening.
| Blood pressure readings for adults age 18 years and older |
| Category | Systollic (mm Hg) | Diastollic (mm Hg) |
| Normal | less than 120 | and less than 80 |
| Prehypertension | 120-139 | or 80-89 |
| Hypertension |
| Stage 1 | 140-159 | or 90-99 |
| Stage 2 | 160+ | or 100+ |
