Everyone has “blood pressure” all the time. It is the pressure of blood against the walls of the main arteries, and is an indication of the amount of work that your heart has to do in order to pump blood around your body.
A blood pressure reading will always have two numbers – one number records the blood pressure when it is at its highest. This is when the heart muscle is squeezing oxygenated blood out of the heart into the arteries and onto the organs and the rest of the body. This reading is referred to as Systolic pressure. The second number -Diastolic pressure - is lower, and is the pressure measurement when the heart is relaxing and refilling.
“Normal” blood pressure readings are usually between 110 – 130 for the systolic measurement and about 80 as the diastolic measurement, though age, emotion and activity can have an effect on the reading. This is expressed as 110 / 80 mmHg. Measurements are taken in milligrams of mercury (mmHg). Approximately one in seven adults in Ireland have high blood pressure.
More info on Blood Pressure
Back to Top
If you have been advised that your blood pressure is 140 / 90 mmHg or more, you should contact your family doctor for advice.
Blood pressure is silent. You don’t “feel” your blood pressure. The only way of finding out if your blood pressure is high is to have it measured. Pressure can vary with age, activity and emotional state. One raised blood pressure reading does not necessarily mean you have “high blood pressure”. Your doctor will usually recheck your blood pressure on a number of occasions before deciding the best treatment.
Blood pressure will vary throughout the day and night. Occasionally your doctor may decide to check your blood pressure over a 24 hour period. This is known as ambulatory blood pressure monitoring. A monitoring device is worn for 24 hours and will record your blood pressure every 15 or 30 minutes.
High blood pressure adds to the workload on the heart and arteries which can cause damage over the years, and can lead to heart attack and stroke at an earlier age than people with normal blood pressure.
If you have been diagnosed with high blood pressure, simple remedies might be sufficient in controlling your blood pressure, such as losing weight, taking regular exercise, stopping smoking, eating a low-fat, low-salt diet and moderate alcohol intake. Along with these life-style alterations your doctor may recommend drug therapy also.
If you have been prescribed drug therapy to control your blood pressure, it is usually for life. You must follow the advice of your doctor and pharmacist.
Drugs used for controlling blood pressure
Back to Top
You may be prescribed one or a combination of the following drugs. It is important to be honest with your doctor in reporting how you feel. A trial of different groups might be necessary at the beginning to find the drug that suits you best and that has the best effect in controlling your blood pressure.
All drugs have potential side-effects, and the list of possible side-effects can look very daunting. Side effects of a widely prescribed drug are usually likely to be minor; otherwise the treatment would not be prescribed. It is important to report any side-effects to your doctor.
Diuretics
Back to Top
Diuretics (water tablets) have been used in the control of high blood pressure since the 1050s. They act on the kidneys, making them excrete excess water and salt in the urine. This group of drugs are often successful in lowering blood pressure. A blood test may be taken a few weeks after starting diuretics to check that dehydration does not lead to a drop in potassium levels.
People taking diuretics find they need to pass water more frequently, especially when they start taking them. This is to be expected, but you should let your doctor know if it is making life more difficult for you or leading to problems with incontinence.
Other side-effects may include loss of appetite, stomach upsets, dehydration, increased blood cholesterol, allergic reaction (in people with asthma), increased uric acid (risk of gout), rise in blood sugar.
Beta Blockers
Back to Top
Beta blockers have been around since the 1960s. They partially block the effects of the hormones adrenaline and noradrenaline and work on different areas, including the heart, kidneys, brain, arteries and nerves which are all responsible for monitoring blood pressure. Usually small doses are effective. Beta blockers must not be stopped abruptly, if you want to stop them, you must consult your doctor and taper them off over a few weeks.
Side-effects tend to be mild and vary from one type to another. They may include light-headedness, pins and needles, cold fingers and toes, drowsiness and fatigue.
Alpha Blockers
Back to Top
Alpha blockers work on the arteries, blocking the effects of adrenaline and noradrenaline. This makes the arteries dilate, reducing the resistance to the flow of blood, which will lead to a fall in blood pressure. This group of drugs are useful for people with diabetes, heart failure and kidney damage. Sometimes people are asked to take the tablet at night time in case the drug causes a rapid drop in blood pressure which would make them dizzy.
Side-effects may include dizziness on standing up or sitting, vertigo, headache, lack of energy, palpitations, urinary frequency, oedema.
Calcium Channel Blockers
Back to Top
Calcium channel blockers – sometimes called calcium antagonists – seem to be effective in controlling high blood pressure in Afro-Caribbean patients and older patients. They can also be used in conjunction with other anti-hypertensive drugs. They have a relaxing effect on the muscles in arteries, making them dilate, which leads to a fall in blood pressure. This group of drugs reduce the workload of the heart and lower its oxygen needs.
Side-effects may include flushing, headache, ankle swelling, fatigue, nausea, dizziness, palpitations, insomnia, rashes, drowsiness, tinnitus.
ACE Inhibitors (Angiotensin-Converting Enzyme Inhibitors)
Back to Top
Angiotensins are hormones produced in the body which regulate blood pressure. By blocking the production of angiotensin 11, this drug group causes the arteries to dilate, thus reducing blood pressure. In addition, this group of drugs also act like diuretics and increase the loss of water and salt in the body, adding to the reduction of blood pressure.
Side-effects may include light-headedness, dizziness especially on sitting up or standing up, rash, allergic reaction.
Angiotensin 11 Receptor Antagonists
Back to Top
These drugs act on the kidneys, adrenal glands, heart, brain and sympathetic nervous system to limit the hormone angiotensin 11, but work by a different mechanism to the ACE inhibitors.
This group of drugs are relatively new and to date seem not to have the side-effects of other groups. Reported side-effect is dizziness. |
