Hypertension is high blood pressure that persists over time.
In certain cases of hypertension, lifestyle modification that focuses on diet changes and exercise can be an effective first line of treatment.
Physicians often prescribe antihypertensive medication to prevent hypertension from progressing to more severe hypertension, and in the process help protect against stroke and coronary events such as heart attack or angina, congestive heart failure, and kidney disease.
The goal of antihypertensive therapy is to use the least intrusive means possible to prevent hypertension, which is defined as high blood pressure that persists over time, from contributing to the development of disease.
WHEN IS IT INDICATED?
Antihypertensive therapy is indicated for people whose blood pressure is consistently more than 140 millimeters of mercury (mm Hg) systolic and 90 mm Hg diastolic.
Because of possible interactions with other drugs, the patient should report any other medications that he or she is taking to a physician. Pregnant women should discuss with their physician whether they are eligible for medications.
RISK FACTORS FOR POSSIBLE COMPLICATIONS
People with a known allergy or sensitivity to a drug are not eligible to take it.
Additionally, people who have liver or kidney disease are at increased risk for complications from angiotensin-converting enzyme (ACE) inhibitors and angiotensin II receptor blockers (ARBs).
WHAT TO EXPECT
Making and maintaining appropriate lifestyle changes can help lower blood pressure. Recommended lifestyle modifications for people with hypertension may include:
Reducing alcohol intake;
Lowering sodium intake;
Maintaining potassium, magnesium, and calcium intake;
Reducing cholesterol and saturated fat intake; and
Considering other factors, such as stress, smoking, and caffeine intake.
If lifestyle modifications alone unable to control hypertension, they may be used to reduce the number and dosage of antihypertensive medications. Medications that treat hypertension include diuretics, beta-blockers, ACE inhibitors, calcium channel blockers, ARBs, direct-acting vasodilators, and peripherally acting agents.
Diuretics: Diuretics stimulate the kidneys to remove water and sodium from the body, thereby decreasing the total volume of blood that the heart has to pump.
Beta-blockers: Beta-blockers block receptor cells that are involved in the release of epinephrine and norepinephrine, agents that stimulate the heartbeat. They lower blood pressure, slow and regulate the heart rate, and reduce the force of heart contractions.
ACE inhibitors: These medications lower blood pressure by inhibiting the formation of substances (angiotensin II and aldosterone) in the kidneys that naturally constrict blood vessels and promote salt and water retention.
Calcium channel blockers: Calcium channel blockers prevent calcium from penetrating muscle tissue in the heart and blood vessels. Since muscles need calcium to contract, calcium channel blockers cause blood vessels to relax and dilate, thereby lowering blood pressure.
ARBs: These drugs prevent angiotensin from entering cells of the heart and blood vessels, dilating blood vessels and reducing the pressure the heart must work against.
Direct-acting vasodilators: Unlike ACE inhibitors and ARBs, vasodilators directly relax the muscles in the walls of blood vessels. Relaxing these muscles in turn allows more blood to flow through the vessels, decreasing the resistance against which the heart must pump.
Peripherally acting agents: Also known as adrenergic inhibitors or nervous system inhibitors, these medications alter nerve function so that blood vessel walls relax, widening the blood vessels and lowering blood pressure.
Physicians often prescribe two or more antihypertensive medicines at the same time, called combination therapy.
POST-TREATMENT GUIDELINES AND CARE
These drugs require medical supervision. The patient should not start or stop taking these medications without first consulting a physician. The patient should tell the physician if any side effects develop from medication therapy.
Typically, people who are prescribed antihypertensive medications return to their physician for a follow-up within 1 to 2 months after starting therapy. Many medications need to be adjusted frequently, based upon a person's response to therapy.