High blood pressure, or hypertension, occurs when excessive force is exerted against artery walls as the heart pumps blood. This silent disease has no symptoms until it has reached an advanced and dangerous stage, at which point it may produce headache, light-headedness, ringing in the ears, and rapid heartbeat. If uncontrolled, hypertension can lead to a heart attack, stroke, or kidney failure. It can also damage the eyes and other organs.
Other Causes of High Blood Pressure
An adrenal tumor called a pheochromocytoma produces adrenaline like hormones that can cause very high blood pressure. A narrowing of the renal artery to the kidney can also raise blood pressure, as can preeclampsia, or toxemia of pregnancy, a serious complication that sometimes develops during the final trimester.
The choice of treatment is determined by the severity of the disease and the presence of complications. Mild to moderate hypertension, generally defined as readings of 140 149/90 104, is initially treated by lifestyle changes Antihypertensive drugs are prescribed when lifestyle changes fail to achieve the desired lowering or when blood pressure is diagnosed in the moderate to severe range of more than 160/105. Although high blood pressure almost always can be controlled, there is no single antihypertensive drug that works for everyone. Treatment may involve taking one or several medications. The classes of antihypertensive drugs are as follows: Diuretics, also called water pills, work by increasing excretion of sodium and water through the kidneys, thereby reducing the total volume of blood. Thiazide diuretics such as hydrochlorothiazide are most commonly used, but in some cases, loop diuretics, such as furosemide (Lasix), are prescribed. These drugs work in a part of the kidney called the loop of Henle and they are generally more potent than thiazide diuretics. Both types of drugs can cause such side effects as lethargy, dizziness, and urinary frequency. Beta blockers lower blood pressure by slowing the heartbeat and reducing the amount of blood pumped during each beat. Propranolol (Inderal), the oldest beta blocker, is still widely used. In addition, there are at least a half-dozen newer ones, including atenolol (Tenormin), metoprolol (Lopressor), nadolol (Corgard), and timolol (Blocadren). A CE (for angiotensin converting enzyme) inhibitors lower blood pressure by blocking the production of angiotensin II, a body chemical that constricts, or narrows, blood vessels. ACE inhibitors include captopril (Capoten) and enalapril (Vasotec). Calcium-channel blockers work by preventing the entry of calcium into the muscle cells that control the arterial walls. This dilates, or opens, the blood vessels, making it easier for blood to flow through them. Drugs in this category include verapamil (Calan) and diltiazem (Cardizem).
Widen, or dilate, arteries. Hydralazine (Apresoline), the oldest antihypertensive drug, is a fast-acting vasodilator; another member of this class is minoxidil (Loniten). These drugs are usually prescribed along with other antihypertensives.
Alpha Blocking Agents
Work through the autonomic nervous system. They block the alpha receptors on the blood vessel walls, which, when stimulated, cause a narrowing of the vessels. Thus, they lower blood pressure by allowing the arteries to open more widely. Two examples are prazosin (Minipress) and terazosin.
Peripheral Adrenergic Antagonists
block the release of norepinephrine, a hormone that raises blood pressure. Reserpine, which is made from rauwolfia, an Indian herb, is the major drug in this category. It is usually prescribed in small doses and used in conjunction with a diuretic.
Centrally Acting Drugs
Lower blood pressure by reducing nerve impulses from the brain. These agents include methyldopa (Aldomet), clonidine (Catapres), and guanabenz (Wytensin). They, too, are combined with other drugs, usually diuretics. Side effects are often a problem with blood pressure medications. However, they can almost always be minimized by changing either the osage or the medication itself. Among the common side effects are unusual tiredness, dizziness or feeling faint upon standing up, nightmares, impotence, and depression. These and any other lingering problems should be reported to a doctor as soon as possible so that the dosage can be changed or an alternative drug can be prescribed.
Patients are taught to lower their heart rate and control other normally involuntary responses. This method is especially useful for reducing stress, which raises blood pressure.
A program of aerobic exercise designed to improve cardiovascular fitness can help to lower blood pressure. Before embarking on such a program, it may be advisable to have an exercise stress test.
Yoga and Meditation
Yoga for high blood pressure like Paschimottanasana, Anuloma Viloma and other relaxation techniques can lower blood pressure. The effects tend to be temporary, so the chosen method should be practiced at least daily.
Thyroidinum, prepared from the thyroid gland, is sometimes recommended; nux vomica is also prescribed for intermittent hypertension.
Mild to moderate hypertension can often be controlled through diet alone. Add minimal or no salt to your food, especially if you are salt sensitive. Use herbs for flavorings or ask your doctor about using potassium chloride as a salt substitute. Also, avoid processed foods that contain any form of sodium. Increase your consumption of vegetables, fruits, and whole grain products, while reducing intake of red meat and other fatty foods.