High blood pressure is a common problem that can have far-reaching consequences for your health. If undiagnosed or left untreated, high blood pressure can lead to serious health problems. It can affect your heart by causing it to enlarge and it can increase the hardening and blocking of your blood vessels. It can also cause strokes and kidney failure. Left untreated for a long time, high blood pressure can even result in damage to your eyes and to impaired vision.

Fortunately, though, it is easy to diagnose. All it takes is a couple of minutes of your time.

Taking Your Measurements
To understand what high blood pressure is and how it affects your body, you must understand how blood pressure is measured. Every time your heart beats, it pushes blood through your arteries and the pressure against your artery walls increases. When your heart rests between beats, the pressure against the artery walls lessens. The point of maximum pressure is called systolic (pronounced sis-tol-ic) pressure and the point of least pressure is called diastolic (pronounced di-as-tol-ic) pressure. When your blood pressure is measured, the systolic pressure is compared with the diastolic pressure. That is why blood pressure readings always come in pairs of numbers, for example, 120/80. The first number refers to the maximum pressure exerted by the blood flow and the second number refers to the resting pressure.

While a blood pressure of less than 130/85 is considered normal for most adults, a variety of factors can affect what is normal for you¹. For example, a normal blood pressure reading for a 25-year-old would not necessarily be considered normal in someone aged 60. And the opposite is true as well. A health care professional, such as a doctor, nurse or pharmacist can help you determine what your blood pressure should be and help you develop a program to reach and maintain that level.

The first step is to find out what your blood pressure reading is. You can't tell if your blood pressure is high by how you feel because high blood pressure has no symptoms. You can feel perfectly fine and still have high blood pressure. That is why it is often referred to as "the silent killer." Some people are confused about this because the medical name for high blood pressure is hypertension. Therefore, they mistakenly think that someone with high blood pressure feels tense or stressed.

A healthy adult should have a blood pressure test once a year, and people with other health conditions should generally be tested more often. One difficulty with blood pressure tests is that many things can affect a person's blood pressure. For example, drinking a cup of coffee or exercising shortly before having the test can result in a temporary rise in blood pressure, leading to a misleading reading. Another factor to consider is that blood pressure is usually higher in the morning than it is in the afternoon. So, don't worry if you get a single high reading; you may need to have your pressure tested several times on different days to get a true picture of your blood pressure level. For some people just being in a doctor's office is enough to raise their blood pressure. Free self-monitoring is available in most Overwaitea Foods pharmacies.

Causes and Treatments
Scientists don't really know what causes most cases of high blood pressure. In a few people, it can result from some other illness or from using certain kinds of drugs such as oral contraceptives, pain relievers, or cough and cold medicines. But in the vast majority of people with high blood pressure the cause just isn't known; this is called essential hypertension.

What is known about high blood pressure is that some people are naturally more prone to developing it for one reason or another. Some of the things that make a person likely to develop it are age, race, a family history of high blood pressure and certain lifestyle factors. Some of these things we can do nothing about. We can't stop the aging process or change our family medical history. But we can make lifestyle changes that will help reduce our chances of developing high blood pressure or of controlling it if our pressure is already high. These changes include:
• Losing excess weight because extra pounds put a strain on the heart.
• Eating a healthy, balanced diet that is low in fat, cholesterol and excessive salt.
• Reducing alcohol intake.
• Participating in a program of regular physical activity with an emphasis on aerobic exercises.
• Reducing the stresses in our lives because stress triggers activity in the nervous system that affects blood pressure.
• Avoiding smoking because nicotine speeds up the heart rate and constricts blood vessels, which causes blood pressure to rise.

Making these lifestyle changes is the first step in treating high blood pressure. And for many people this will be enough to bring their blood pressure down to a normal level. But, when it is not enough, antihypertensive medications (commonly called blood pressure pills) play an important part in the treatment program. When used in combination with a program of lifestyle changes, these pills usually bring an elevated blood pressure down to normal levels.

Controlling high blood pressure is a commitment you make for a lifetime. It means incorporating healthy habits and taking medication as prescribed by your doctor. There are a variety of different blood pressure medications on the market. The six main classes include: diuretics, beta-blockers, angiotensin converting enzyme (ACE) inhibitors, angiotensin II receptor blockers, calcium channel blockers and alpha-adrenergic blockers.

Diuretics increase the amount of fluid excreted from your body resulting in a decrease in blood volume. Low-dose diuretics tend to be well tolerated and less associated with the unwanted side effects compared with the higher-dose diuretics². Examples of this class of medication are hydrochlorothiazide and furosemide³.

Beta-blockers lower blood pressure via a method that is still not fully understood. Generally, beta-blockers (for example, pindolol, nadolol or propanolol) should not be used in those with obstructive airway diseases (for example, asthma), diabetes and peripheral vascular diseases. However, these people may be treated with a more target specific beta-blocker (for example, bisoprolol, atenolol, metoprolol or acebutolol) if they are prescribed at low doses. It is important that you don't stop taking this medication on your own, because it can cause serious negative effects³.

ACE inhibitors block the production of angiotensin II, a powerful vasoconstrictor that causes narrowing of the blood vessels. Less narrowing means lower pressure through the vessels³. This class of medication is especially effective in reducing the fatality associated with heart failure². Examples of ACE inhibitors are enalapril, lisinopril and quinapril⁴.

Whereas the ACE inhibitors block the production of angiotensin II, angiotensin II receptor blockers stop the already produced vasoconstrictor from working⁵. Angiotensin II receptor blockers share many features with ACE inhibitors and they tend to have fewer side effects than ACE inhibitors². Losartan and valsartan are examples of this class⁴.

Calcium channel blockers relax the muscles around the blood vessels, which result in vasodilation (widening of the blood vessels)³. Examples of this class of medication are verapamil, nifedipine and diltiazem⁴.

Alpha-adrenergic blockers come in two forms. One type blocks certain activities in the brain causing a decrease in heart rate, the resistance in the blood vessels and the amount of blood that's pumped out with each beat. Examples include clonidine and methyldopa. The other type works outside the brain (for example, prazosin, terasosin or doxazosin) to lower blood pressure. Both types of alpha-adrenergic blockers at low doses are effective in treating mild high blood pressure³.

Sometimes blood pressure medicines cause side effects. Because high blood pressure has no symptoms, the side effects from the medicine may make you feel worse than you did before you started taking it. If this happens to you, discuss it with your doctor or pharmacist. There are a number of different types of antihypertensive medication and each works in a different way. Eliminating side effects may be as simple as changing the type of pill you take. Some people find that their bodies adjust to the medication after they have taken it for a while and the side effects just don't bother them as much. But, no matter what, don't decide on your own to stop taking your medicine, because stopping the medicine abruptly can be dangerous.

Unfortunately, onlyabout half of the people with high blood pressure continue to take their medication properly for as long as they need it. Those who stop the treatment or who don't follow their doctor's instructions about how to take their medicine properly put their health at risk. If you have any questions about your medication or if you are having any difficulty with side effects, ask your doctor or pharmacist for advice. Most medication problems have a solution, it's just a matter of finding the right drug for your particular case. High blood pressure is controllable but it isn't usually curable. You must continue to manage your high blood pressure through lifestyle changes and, when necessary, medication.

Nutrition Tours
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A Few Words of Caution
For the same reasons it's important to take your blood pressure medicine exactly as prescribed, it is critical that you don't take medication prescribed for anyone else. The different types of antihypertensive medication work in different ways and what is right for someone else may not be right for you. Likewise, you should not share your blood pressure medicine with anyone else. Not only may the medicine not do any good, it may do a great deal of harm.

Another thing to keep in mind is that if you see more than one doctor (for example, if you see one or more specialists in addition to your family doctor) make sure that all of your doctors know that you have high blood pressure and that you are on medication. Some drugs used for other conditions can raise blood pressure or interfere with blood pressure medications. If you use any over-the-counter medications, ask your pharmacist if it is safe to take them when you are on blood pressure medication because some of these products can raise blood pressure or interact with antihypertensive medications as well.

Seeking Information
If you have any questions about blood pressure or about your treatment, your health care providers can answer your questions. Your doctor knows the details of your personal medical history and can answer questions about your treatment plan. Your pharmacist is a medication expert with years of training in this specialized field and can answer questions about drug therapy, how antihypertensive medications work and what medicines (both prescription and non-prescription) you should not use when you are on blood pressure medication.

Overwaitea Foods pharmacists can also introduce you to the benefits of the Healthtouch® computer kiosk - an easily accessible, user-friendly and authoritative source of the latest knowledge on health and medicines at the touch of your fingertips. Healthtouch® kiosks are located in all of our pharmacies. And when you have found the information you're looking for, you can print it up and take it with you.

Additional information about high blood pressure and heart disease is available from:

The material in this patient information pamphlet has been supplied by a professional medical writer and reviewed by a licensed medical practitioner and is for information purposes only.Overwaitea Food Group is not responsible for errors, omissions or inconsistencies with respect to the information contained in this pamphlet and does not accept any liability whatsoever for reliance by the reader on the information contained herein.

References

1. www.nhlbi.nih.gov/health/public/heart/hbp/prevhbp/index.htm#introd (July 17, 2000)
2. 1999 World Health Organization - International Society of Hypertension Guidelines for the Management of Hypertension. (July 17, 2000)
3. Schwinghammer T. L. Hypertension, In: Wells, B., Dipiro J. T., Schwinghammer T. L., and Hamilton C.W. (eds.). Pharmacotherapy Handbook, 2nd ed. Connecticut: Appleton and Lange, 2000: 94 - 113.
4. Carruthers S. G. Hypertension, In: Gray J. (ed.). Therapeutic Choices, 2nd ed. Canadian Pharmacists Association, 1998: 228 - 236.