High blood pressure, or hypertension, is defined in an adult as a systolic pressure of 140 mm Hg or higher and/or a diastolic pressure of 90 mm Hg or higher. Blood pressure is measured in millimeters of mercury (mm Hg).

Blood pressure (mm Hg)	Normal	Prehypertension	Hypertension
Systolic (top number)	less than 120	120–139	140 or higher
Diastolic (bottom number)	less than 80	80–89	90 or higher

mm Hg = millimeters of mercury

High blood pressure directly increases the risk of coronary heart disease (which leads to heart attack) and stroke, especially along with other risk factors.

High blood pressure can occur in children or adults. It's particularly prevalent in African Americans, middle-aged and elderly people, obese people and heavy drinkers. People with diabetes mellitus, gout or kidney disease have hypertension more often.

High blood pressure usually has no symptoms. It's truly a "silent killer." But a simple, quick, painless test can detect it.

How Can I Reduce High Blood Pressure?

• Lose weight if you’re overweight.
• Eat a healthy diet low in saturated fat, cholesterol and salt.
• Be more physically active.
• Limit alcohol to no more than one drink per day for women or two drinks a day for men.
• Take medicine the way your doctor tells you.
• Know what your blood pressure should be and work to keep it at that level.

What should I know about medicine?

Your doctors may prescribe different types of medicine for you. Don’t be discouraged if you need to take blood pressure medicine from now on. Sometimes you can take smaller doses after your blood pressure is under control, but you may always need some treatment. What’s most important is that you take your medicine exactly the way your doctor tells you to. Never stop treatment on your own. If you have problems or side effects with your medicine, talk to your doctor.

If you have heart disease or have had a stroke, members of your family also may be at higher risk. It’s very important for them to make changes now to lower their risk. Talk to your doctor, nurse or other health-care professionals.