There are three ways of treating high blood pressure:

Reduce the amount of water in the body

Fluid overload can cause your blood pressure to increase. This is because your blood contains more water than normal, increasing the pressure on your blood vessels (the tubes that carry blood around your body). Correcting fluid overload, by dialysis and by restricting fluid intake, will reduce the blood pressure. Diuretic medication (also called "water pills") tends to increase the flow of urine and thus can reduce blood pressure.

Vasodilators

Vasodilators lower the blood pressure by causing the arteries to widen. There are several different types of vasodilator drugs including:

Beta-blockers

These drugs reduce the heart rate (the number of heart beats per minute). They also lower the blood pressure, although it is not clear how they do this.

Commonly used beta-blockers include atenolol, metoprolol, and propranolol.