High blood pressure, or hypertension, is often called the silent killer because it usually causes no symptoms while quietly damaging your arteries, heart, brain, kidneys, and eyes. Many people feel completely fine and only discover they have it during a routine check. Understanding your numbers and acting early is one of the most powerful things you can do for your long-term heart and stroke health.
What the numbers mean
A blood pressure reading has two numbers, written as systolic over diastolic and measured in millimeters of mercury (mmHg). The top number is the pressure when your heart beats; the bottom is the pressure when it rests. General categories used by many guidelines are:
- Normal: around 120/80 mmHg or below
- Elevated: top number 120 to 129 with a bottom under 80
- Stage 1 hypertension: roughly 130 to 139 over 80 to 89
- Stage 2 hypertension: 140/90 or higher
- Very high readings (often 180/120 or above) need urgent medical attention
Thresholds vary slightly between countries and guidelines, so your clinician interprets your readings in the context of your overall risk.
Seek emergency care
If your blood pressure is extremely high (often 180/120 or above) and you have chest pain, severe headache, shortness of breath, vision changes, weakness, or trouble speaking, call 911 (US/Canada), 999 (UK), or 112 (EU) right away. This can signal a hypertensive emergency.
Why it is so dangerous
Persistently high pressure forces the heart to work harder and stiffens and narrows arteries over time. This raises the risk of heart attack, stroke, heart failure, kidney disease, and vision loss. Because the damage is gradual and painless, hypertension can progress for years before it is caught.
Measuring at home the right way
- Sit quietly for five minutes before measuring, feet flat and back supported.
- Rest your arm on a table at heart level.
- Avoid caffeine, exercise, and smoking for 30 minutes beforehand.
- Take two or three readings a minute apart and record them.
- Measure at the same times each day and share the log with your doctor.
Lifestyle steps that help
- Reduce salt and eat more vegetables, fruit, and whole grains
- Stay physically active most days of the week
- Maintain a healthy weight
- Limit alcohol and avoid tobacco
- Manage stress and prioritize sleep
When lifestyle changes are not enough, doctors may recommend medication. There are several classes of blood pressure medicine, and the right choice depends on your age, other conditions, and how you respond. Only a licensed clinician should start, adjust, or stop these medications. Never change a dose on your own.
Talk to a doctor
If your readings are high or you want help building a plan, a verified doctor on iHealix can review your numbers, history, and goals and guide treatment safely.
This article is for general information only and is not a substitute for advice from a licensed doctor or pharmacist.