High blood pressure (hypertension) is very common and the proportion of both men and women with high blood pressure increases steadily with age.
High blood pressure sneaks up on you. Except at extreme levels, high blood pressure is a silent condition causing no symptoms. If you wait until you feel unwell, you may have left things too late, therefore it is important to get regular blood pressure checks.
High blood pressure can cause the heart muscle to enlarge and the heart to weaken. It also damages the blood vessels, especially if you also have raised blood cholesterol or diabetes, or if you smoke cigarettes.
Narrowing or blockage of the blood vessels is a hallmark of cardiovascular diseases such as heart attack, stroke, and poor circulation in the legs — which can cause pain and even gangrene.
High blood pressure can increase the risk of cardiovascular disease by 2 to 4 times. The higher the blood pressure, the higher the risk of both coronary heart disease and stroke. High blood pressure can also damage your kidneys.
When the heart pumps, it produces pressure inside the arteries and moves the blood forward. This is called systolic pressure. Then the heart relaxes as it fills again and the pressure in your arteries falls. This is called diastolic pressure.
The pressure is measured in millimetres of mercury (mmHg). Acceptable blood pressure is often quoted as being less than 140 mmHg (systolic pressure) over 90 mmHg (diastolic pressure) — written as 140/90.
Doctors often subdivide this category into:
High blood pressure, or hypertension, means that the systolic or diastolic pressure or both are above the normal range. A reading above 140/90 mmHg is usually considered to be ‘hypertension’, though hypertension is further divided up by doctors into mild, moderate or severe depending on the blood pressure reading. The divisions are as follows.
When deciding whether your blood pressure reading is of concern or not, your doctor will take various factors, particularly your age, into account. He or she will also want to check your pressure on more than one occasion before deciding whether you have high blood pressure or not. Your doctor may ask you to check your blood pressure at home — machines can be purchased from some pharmacies.
It is important to remember that our blood pressure rises at certain times, and that is not necessarily a bad thing. During exercise, for example, the pulse rate and blood pressure increase in order to carry extra blood and oxygen to the muscles. When you finish exercising, the blood pressure returns to normal.
Blood pressure also rises with excitement, anger or fear but this usually does not last long.
There is only one way: get your blood pressure measured. See your family doctor for a blood pressure check. Every adult should have their blood pressure checked regularly. Your doctor will advise you how often. This depends on your age, your general health and whether you are taking any herbal products, supplements or medicines, including the contraceptive pill.
In most people, there is no obvious cause. High blood pressure often runs in families but occasionally kidney or other diseases may be responsible. Other contributory factors include:
Medicines can help control high blood pressure but do not cure it. Usually blood pressure medicines need to be taken long-term.
You cannot tell how your blood pressure is doing by the way you feel. Regular check-ups are essential and it is unwise to change your own dose of tablets.
To control blood pressure successfully, you may need 2 or more medicines, each working in a different way. Using a combination of medicines often means lower doses can be used. We all react differently to medicines, so it may take some time to find the combinations and doses that suit you best.
It is important to tell your doctor about any other health products you are taking — this includes eyedrops, ointments, over-the-counter preparations, herbs and supplements.
It is also important to follow your doctor’s instructions about taking blood pressure medicines.
Like all medicines, those for high blood pressure may occasionally cause side effects. These vary among the medications and from patient to patient, and often decrease with time or by your doctor adjusting your dosage. If your blood pressure gets too low on the medicine, you may feel faint or dizzy. If you sit or lie down, these feelings should pass. You may also notice a feeling of excessive tiredness or heaviness in your legs.
Some medicines act more strongly when you stand and those with long action may make you feel faint if you get up at night, if you leap out of bed too quickly in the morning, if you suddenly exert yourself or when you get out of a hot shower or bath. Standing up slowly can help avoid this problem.
You should let your doctor know about any reactions you have to the medicines. With the range of blood pressure medicines now available, it is nearly always possible to find one that will give you minimal or no side effects.
If you are prescribed another medicine, you should ask whether it might affect your blood pressure treatment. Medicines that may affect blood pressure control include:
Always tell the anaesthetist and surgeon what treatment you are having and they will make any necessary adjustments. Patients on medicines for high blood pressure usually have no special problems with surgical operations. If you are asked to fast before an operation, check with your surgeon or anaesthetist whether you can still take your pills with a sip of water.
All adults should have their blood pressure checked regularly. Your doctor may check your blood pressure when you make routine visits to the surgery.
If you fall into one of the categories listed below, you should have your blood pressure checked more regularly.
If you have had high blood pressure, you need to have regular checks throughout your life. This is true even if you are not currently receiving any treatment, or if you are being treated by diet and lifestyle changes or with medicines.
Your doctor will tell you how often is advisable, but generally speaking it will be at least every 6 months.
In the early stages of drug treatment, you may need to be seen weekly or fortnightly, but once your blood pressure is controlled checks may be spaced out to once every 3 or 6 months.
If you have high blood pressure, it’s also worth being checked for other conditions that may further increase your risk of cardiovascular disease, such as diabetes and high cholesterol.
High blood pressure often runs in families. Suggest to others in your family that they also have their blood pressure measured.
Last Reviewed: 12 June 2009