If adequate blood pressure control is not achieved with diet, exercise, alcohol abstinence, and sodium restriction, then medication is necessary. There are many types of blood pressure medications. Most antihypertensive medications can cause side effects. Some of the more common side effects are lethargy, lightheadedness, rash, cough, change in bowel habits or change in libido.

The main types of antihypertensives are:

Diuretics - (water pills) which work on a portion of the kidney preventing the reabsorption of sodium. When sodium is lost in the urine, there is an obligatory loss of water with it. As sodium is taken from the artery walls, the walls relax and the blood pressure decreases.

Beta-blockers - these drugs block some of the effects of adrenalin or epinephrine and similar chemicals known as neurotransmitters. By blocking the action of these agents, the heart rate and blood pressure are reduced.

ACE - angiotensin convertin enzyme inhibitors - prevent the hormone angiotensin II from being produced by angiotensin I. Angiotensin II causes blood vessels to constrict thereby raising the blood pressure.

ARB - angiotensin receptor blockers - similarly prevent angiotensin from acting on the blood vessels but by blocking the receptor site itself.

Calcium Channel Blockers - keep calcium from entering the muscle cells of the heart and blood vessels which allows the vessels to relax and dilate and the blood pressure to decrease. Calcium channel blockers do not affect the bones or calcium level in the blood.

Alpha blockers - block the alpha effect of epinephrine. This decreases the nervous system's ability to narrow or constrict the blood vessels which produces a lower blood pressure.

Vasodilators - act directly on the blood vessels to make them relax, thus lowering the blood pressure.

See information on specific drugs in the drug information section to define which class of drug you are taking.

The information listed above is for educational purposes only and should not be used as a substitute for a consultation or visit with your family physician or other health care provider.