Nearly one in three adults in the United States has high blood pressure, also called hypertension. High blood pressure is dangerous because it increases the risk of stroke, heart attack, heart failure, kidney failure, death.
"High blood pressure is often called the 'silent killer' because it usually has no symptoms until it causes damage to the body," says Douglas Throckmorton, M.D., Deputy Director of FDA's Center for Drug Evaluation and Research. Many studies have shown that lowering the blood pressure with drugs decreases that damage.
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Blood is carried from the heart to all parts of the body in vessels called arteries. Blood pressure is the force of the blood pushing forward through the body and against the walls of the arteries. The higher the blood pressure, the greater the risk of stroke, heart attack, heart failure, kidney failure, and death.
Blood pressure is made up of two numbers:
The "top" number is the systolic blood pressure—the pressure while the heart is pumping blood out.
The "bottom" number is the diastolic blood pressure—the pressure while the heart is filling up with blood, getting ready to pump again.
It was once believed that only diastolic pressure (the "bottom" number) was important, but this is not true. Elevated systolic pressure alone, particularly common in older people, is just as dangerous as elevations of both systolic and diastolic pressure.
Blood pressure is elevated for two main reasons:
too high blood volume
too narrow blood vessels due to a substance our kidneys make called angiotensin.
Most of the time, the cause of a person's high blood pressure is unknown. Once it develops, high blood pressure usually lasts the rest of the person's life. But it is treatable.
Some people can lower blood pressure by losing weight, limiting salt intake, and exercising, but for most people, these steps are not enough. Most people need medication for blood pressure control, and will probably need it all their lives.
Types of Medications
FDA has approved many medications to treat high blood pressure, including
Diuretics, or "water pills," which help the kidneys flush extra water and salt from your body and decrease blood volume
Several kinds of drugs that block the effects of angiotensin, reducing blood pressure by relaxing blood vessels, including
Angiotensin converting enzyme (ACE) inhibitors
Angiotensin II receptor blockers (ARBs)
Beta blockers, which also cause the heart to beat with less force
Drugs that directly relax the blood vessels, including
Calcium channel blockers (CCBs)
Other direct dilators (relaxers) of blood vessels
Alpha blockers, which reduce nerve impulses that tighten blood vessels
Nervous system inhibitors, which control nerve impulses from the brain to relax blood vessels
Many people with high blood pressure will need more than one medication to reach their goal blood pressure. Your health care provider can tell you if you should be on medication and, if so, which drug(s) may be best for you.