The most commonly prescribed drugs for hypertension drugs are:
Diuretics - or "water pills" such as thiazide, hydroclorathiazide, chlorathalidone and indapamide) which work by helping the kidneys to pass accumulated salt and water, thereby decreasing the amount of fluid in the body and lowering blood pressure. Diuretics also cause blood vessels to dilate, reducing the resistance to blood flow, and therefore its pressure. Some types of diuretics cause the kidneys to excrete potassium so potassium supplements may be needed.
Beta-blockers - such as propranolol, atenolol, nadolol, pindolol and labetolol which relax the heart by blocking the actions of hormones such as adrenaline and noradrenaline which make the heart pump harder.
Alpha-blockers - such as prazosin which also block the effects of adrenalin and noradrenaline on the blood vessels, relaxing and dilating them.
Vasodilators - such as hydralazine and minoxidil which relax the smooth muscle of the arteries, causing them to dilate and thereby reducing the resistance to blood flow.
Calcium-channel blockers - such as nifedipine, nicardipine, verapamil and diltiazem which work by blocking the flow of calcium in the muscles of the heart and blood vessels, causing the blood vessels to dilate.
Angiotensin converting enzyme (ACE) inhibitors - such as captopril, enalapril, perindopril, ramipril, quinapril and lisinopril, which block the action of the hormone angiotensin II, that narrows blood vessels.
Angiotensin receptor blockers - such as candesartan, irbesartan, telmisartan, eprosartan behave in the same way as ACE inhibitors.
The drugs methyldopa and clonidine also dilate blood vessels, but do so by acting on the part of the brain that controls blood pressure through nerve impulses to the heart and blood vessels), rather any direct effects on the heart and blood vessels themselves.
Being overweight is a risk factor for having high blood pressure, and that risk is increased further if you are obese. The most scientific way to measure your weight is to calculate your Body Mass Index (BMI) - this is your weight in kilograms divided by your height in metres squared - people with a BMI of between 25-30 are considered overweight, and those with an index above 30 are considered to be obese - people with a BMI of 40 or more are morbidly obese.
The best way to tackle obesity is to reduce the amount of calories that you eat, and ensure that you take regular exercise.
It is estimated that 1 in 3 American adults and 40% of adults in England have hypertension; hypertension affects almost three million Australians over the age of 25 and approximately one in five Canadians older than 20.