Medications for Treatment of High Blood Pressure

Adrenergic blockers include alpha-blockers, beta-blockers, alpha-beta blockers, and peripherally acting adrenergic blockers. These medications block the effects of the sympathetic division, the part of the autonomic nervous system Autonomic nervous system The peripheral nervous system consists of more than 100 billion nerve cells (neurons) that run throughout the body like strings, making connections with the brain, other parts of the body, and... read more that can rapidly respond to stress by increasing blood pressure.

Beta-blockers are no longer considered first-line medications for the treatment of hypertension. They are sometimes useful people who have had a heart attack Acute Coronary Syndromes (Heart Attack; Myocardial Infarction; Unstable Angina) Acute coronary syndromes result from a sudden blockage in a coronary artery. This blockage causes unstable angina or a heart attack (myocardial infarction), depending on the location and amount... read more , have a rapid heart rate, angina pectoris Angina Angina is temporary chest pain or a sensation of pressure that occurs while the heart muscle is not receiving enough oxygen. A person with angina usually has discomfort or pressure beneath the... read more (chest pain due to inadequate blood supply to the heart muscle), or migraine headaches Migraines A migraine headache is typically a pulsating or throbbing pain that ranges from moderate to severe. It can affect one or both sides of the head. It is often worsened by physical activity, light... read more .

Alpha-blockers are also no longer used as the main therapy for hypertension because they do not decrease the risk of death. Peripherally acting adrenergic blockers are usually only used if a third or fourth type of medication is needed to control blood pressure.

Angiotensin-converting enzyme (ACE) inhibitors lower blood pressure in part by dilating arterioles. They dilate arterioles by preventing the formation of angiotensin II, a chemical produced in the body that causes arterioles to constrict. Specifically, these inhibitors block the action of angiotensin-converting enzyme, which converts angiotensin I to angiotensin II (see figure ). These medications are particularly useful for people with coronary artery disease Overview of Coronary Artery Disease (CAD) Coronary artery disease is a condition in which the blood supply to the heart muscle is partially or completely blocked. The heart muscle needs a constant supply of oxygen-rich blood. The coronary... read more or heart failure Heart Failure (HF) Heart failure is a disorder in which the heart is unable to keep up with the demands of the body, leading to reduced blood flow, back-up (congestion) of blood in the veins and lungs, and/or... read more , young people, people with protein in their urine because of chronic kidney disease Chronic Kidney Disease Chronic kidney disease is a slowly progressive (months to years) decline in the kidneys’ ability to filter metabolic waste products from the blood. Major causes are diabetes and high blood pressure... read more or diabetic kidney disease Kidney damage in diabetes People with diabetes mellitus have many serious long-term complications that affect many areas of the body, particularly the blood vessels, nerves, eyes, and kidneys. (See also Diabetes Mellitus... read more , and men who develop sexual dysfunction as a side effect of another antihypertensive medication.

Angiotensin II receptor blockers (ARBs) lower blood pressure by a mechanism similar to the one used by angiotensin-converting enzyme inhibitors: They directly block the action of angiotensin II, which causes arterioles to constrict. Because the mechanism is more direct, angiotensin II receptor blockers may cause fewer side effects than angiotensin-converting enzyme inhibitors.

Calcium channel blockers cause arterioles to dilate by a completely different mechanism. They are particularly useful for people of African ancestry and older people. Calcium channel blockers are also useful for people who have angina pectoris Angina Angina is temporary chest pain or a sensation of pressure that occurs while the heart muscle is not receiving enough oxygen. A person with angina usually has discomfort or pressure beneath the... read more , certain types of rapid heart rate, or migraine headaches Migraines A migraine headache is typically a pulsating or throbbing pain that ranges from moderate to severe. It can affect one or both sides of the head. It is often worsened by physical activity, light... read more . Calcium channel blockers may be short-acting or long-acting. Short-acting calcium channel blockers are not used to treat high blood pressure. Reports suggest that people using short-acting calcium channel blockers may have an increased risk of death due to heart attack, but no reports suggest such effects for long-acting calcium channel blockers.

Centrally acting alpha-agonists lower blood pressure through a mechanism that somewhat resembles that of adrenergic blockers. By stimulating certain receptors in the brain stem, these agonists inhibit the effects of the sympathetic division of the nervous system. These medications are rarely used now.

Direct vasodilators dilate blood vessels by another mechanism. A medication of this type is almost never used alone; rather, it is added as a second medication when another medication alone does not lower blood pressure sufficiently.

A thiazide or thiazide-like diuretic (such as chlorthalidone or indapamide) may be the first medication given to treat high blood pressure. Diuretics can cause blood vessels to widen (dilate). Diuretics also help the kidneys eliminate sodium and water, decreasing fluid volume throughout the body and thus lowering blood pressure.

Thiazide diuretics cause potassium to be excreted in the urine, so people sometimes must also take potassium supplements or a diuretic that does not cause potassium loss or that causes potassium levels to increase (a potassium-sparing diuretic). Usually, potassium-sparing diuretics are not used alone because they do not control blood pressure as well as thiazide diuretics do. However, the potassium-sparing diuretic spironolactone is sometimes used alone.

Diuretics are particularly useful for people of African ancestry, older people, people with obesity, and people with heart failure or chronic kidney disease.