What should I do now?
Call 911
Call 911 for chest pressure, severe trouble breathing, or sudden weakness, trouble speaking, or vision changes. Do not wait for a BP reading. Very high BP with these symptoms is an emergency.
Contact your care team
If the top number is above 180 or the bottom number above 120 without concerning symptoms, repeat after at least 1 minute. If still this high, contact your clinician immediately. Do not take extra medicine without instructions.
Keep your care plan
Keep your treatment and follow-up plan. Bring questions, readings, and your medication list.
SECTION 1
What is high blood pressure?
Blood pressure is the force of blood pushing against the walls of your arteries. Your heart creates this pressure as it pumps blood throughout your body.
High blood pressure, also called hypertension, means this pressure stays higher than it should over time. This makes your heart work harder and can gradually damage your blood vessels and organs.
What do the two numbers mean?
A reading such as 120/80 contains two measurements:
- Top number—systolic: Pressure when your heart squeezes.
- Bottom number—diastolic: Pressure while your heart relaxes between beats.
Blood pressure is measured in millimeters of mercury, written as mm Hg. Either number can be too high.
Understanding your numbers
Normal
Top number: Below 120
Bottom number: And below 80
Elevated
Top number: 120–129
Bottom number: And below 80
Stage 1 hypertension
Top number: 130–139
Bottom number: Or 80–89
Stage 2 hypertension
Top number: 140 or higher
Bottom number: Or 90 or higher
If the numbers fall into different categories, use the higher category. For example, 125/92 is Stage 2 hypertension because the bottom number is high.
One elevated reading does not usually establish a diagnosis. Your care team looks at repeated measurements and the circumstances in which they were taken.
Why does it matter?
Over time, uncontrolled blood pressure increases the risk of:
- Heart attack and stroke.
- Thickening of the heart muscle and heart failure.
- Kidney damage.
- Vision problems.
Treatment protects your future health—even when you feel completely well.
Updated October 2026. Educational information; your own care plan may differ. Medical illustrations are simplified examples for teaching.