More than half of Americans over 60 years old have high blood pressure, or hypertension, a condition that greatly contributes to serious health problems, including stroke, heart attack and kidney failure.
While a better diet and more activity may help control high blood pressure, studies have shown that medication is often necessary to control the condition. Doctors prescribe six classes of drugs for high blood pressure, and on average, each drug may reduce blood pressure by 10 to 15 percent.
Sometimes one drug is enough; other times it takes more than one. Also, many of these drugs are used to treat conditions related to high blood pressure, including heart and kidney failure.
Diuretics
Often called the first line of defense against high blood pressure, "water pills" work by flushing excess water and salt from the body. They treat heart failure, lower high blood pressure associated with aging and lower the blood pressure when the heart is contracting--the systolic or high number in the reading.
Side effects may include low potassium levels, increased uric acid in the blood, glucose intolerance, elevation of lipids in the blood, electrolyte disturbances and impotence.
Beta Blockers
Beta blockers work by lowering the heart rate and, therefore, the amount of blood it pumps. They are often given to patients with angina, heart failure, history of heart attacks, heart rhythm problems and migraines.
Side effects may include heart failure, wheezing, irregular heartbeat, poor circulation, insomnia, fatigue and high triglycerides.
ACE Inhibitors
ACE inhibitors lower blood pressure by slowing activity of an enzyme--angiotensin converting enzyme, or ACE. Blocking this enzyme causes blood vessels to enlarge, thus lowering blood pressure.
These drugs are used to treat heart failure, diabetic conditions and kidney disease.
Side effects may include cough, tissue swelling, rash, loss of taste and low white blood cell counts.
Calcium Channel Antagonists
Often called calcium channel blockers, these drugs work by preventing calcium from entering the cells of the heart and blood vessel walls. As a result, the heart and blood vessels relax, lowering blood pressure.
These drugs often are prescribed to older patients and those with high systolic blood pressure (measured when the heart is contracting). Side effects may include headache, flushing, swelling of the gums, fluid retention and insufficient blood supply to the heart.
Alpha-Blockers
Also called alpha-adrenergic antagonists, these drugs work by preventing the hormone norepinephrine from tightening the muscles in the walls of small blood vessels. These drugs are also used to treat prostate enlargement.
Side effects include drowsiness, fatigue, headache, weakness and a drop in blood pressure while lying down.
Angiotensin-Receptor Antagonists
These drugs block angiotensin II, a substance that may narrow blood vessels and also may increase sodium and water in the body. In addition to treating high blood pressure, they are used in patients who have congestive heart failure or kidney failure caused by diabetes. They are also given to patients who develop coughs with ACE inhibitors.
Side effects include high potassium levels and, rarely, tissue swelling.
