Diuretics are among the oldest known medications for treating hypertension.

They work in the tiny tubes (tubules) of the kidneys to remove salt from the body. Water (fluid) also may be removed along with the salt. Diuretics may be used as single drug treatment for hypertension.

Usually low doses of diuretics are used in combination with other anti-hypertensive medications.

The most commonly used diuretics to treat hypertension include hydrochlorothiazide (Hydrodiuril), the loop diuretics furosemide (Lasix) and torsemide (Demadex), the combination of triamterene and hydrochlorothiazide (Dyazide), and metolazone (Zaroxolyn. Note that diuretics probably should not be used in pregnant women.

Some of these drugs may decrease your body's supply of a mineral called potassium. Symptoms such as weakness, leg cramps or being tired may result. Eating foods containing potassium may help prevent significant potassium loss. Some people suffer from attacks of gout after prolonged treatment with diuretics. This side effect isn't common and can be managed by other treatment.

In people with diabetes, diuretic drugs may increase the blood sugar level.

Impotence may also occur in a small percentage of people.

Beta-blockers reduce nerve impulses to the heart and blood vessels. This makes the heart beat slower and with less force. Blood pressure drops and the heart works less hard.

Examples of beta-blockers include atenolol (Tenormin), propranolol (Inderal), metoprolol (Toprol), nadolol (Corgard), betaxolol (Kerlone), acebutolol (Sectral), pindolol (Visken), and bisoprolol (Zebeta).

Angiotensin converting enzyme (ACE) inhibitors prevent the formation of a hormone called angiotensin II, which normally causes blood vessels to narrow. The ACE inhibitors cause the vessels to relax and blood pressure goes down.

Examples of ACE inhibitors include enalapril (Vasotec), captopril (Capoten), lisinopril (Zestril and Prinivil), benazepril (Lotensin), quinapril (Accupril), perindopril (Aceon), ramipril (Altace), trandolapril (Mavik), fosinopril (Monopril), and moexipril (Univasc ).

May cause a skin rash; loss of taste; a chronic dry, hacking cough; and in rare instances, kidney damage.

ARB drugs work by blocking the angiotensin receptor (binder) on the arteries to which activated angiotensin must bind to have its effects. As a result, the angiotensin is not able to work on the artery.

Examples of ARB drugs include losartan (Cozaar), irbesartan (Avapro), valsartan (Diovan), candesartan (Atacand), olmesartan (Benicar), telmisartan (Micardis), and eprosartan (Teveten).

These drugs may cause occasional dizziness.

CCBs keep calcium from entering the muscle cells of the heart and blood vessels. This causes the blood vessels to relax and pressure goes down.

Three major types of calcium channel blockers are used. One type is the dihydropyridines, which do not slow the heart rate or cause other abnormal heart rates or rhythms (cardiac arrhythmias). Examples of these drugs include amlodipine (Norvasc), sustained release nifedipine (Procardia XL, Adalat CC), felodipine (Plendil), and nisoldipine (Sular).
The other two types of calcium channel blockers are referred to as the non-dihydropyridine agents. One type is verapamil (Calan, Covera, Isoptin, Verelan) and the other is diltiazem (Cardizem, Tiazac, Dilacor, and Diltia).

May cause palpitations, swollen ankles, constipation, headache or dizziness. Side effects with each of these drugs differ a great deal.

Alpha-blockers reduce nerve impulses to blood vessels, which allows blood to pass more easily, causing the blood pressure to go down.

May cause fast heart rate, dizziness or a drop in blood pressure when you stand up.