Hypertension (the medical term for high blood pressure) that isn’t treated can greatly increase a person’s risk of developing coronary heart disease (narrowing of the arteries that supply your heart), heart failure, kidney failure and stroke, so it is important that it is managed and treated.
Treatment for high blood pressure includes:
- lifestyle measures; and
If you have high blood pressure, your doctor will check if you have any other cardiovascular risk factors, such as diabetes, smoking, high cholesterol, or a family history of angina or heart attack, so that your absolute risk of cardiovascular (heart and blood vessel) disease can be determined.
The treatment that is most suitable for you will depend on your blood pressure readings plus your absolute risk of cardiovascular disease, as well as whether you have any effects from having high blood pressure.
In addition to treating high blood pressure, your doctor will recommend treatments for any other risk factors you have for cardiovascular disease. Some people with high blood pressure that is difficult to treat may need to be referred to a cardiologist (specialist in high blood pressure and heart conditions).
Making lifestyle changes
All people with high blood pressure should follow the recommended lifestyle advice given by their doctor.
For some people, making some simple lifestyle changes may be all that’s needed to bring blood pressure down. You may not need medicines, particularly if your doctor considers you’re at a low risk of developing complications. In those who are taking blood pressure medicines, making lifestyle changes can enhance their effectiveness, and in some cases the dose may be able to be reduced or medicines stopped altogether.
The following steps can reduce high blood pressure and also prevent many people from developing it in the first place. They can also improve overall health and reduce the risk of developing cardiovascular disease.
Lose weight (if you are overweight) and follow a healthy eating plan
Losing even a small amount of weight helps many people reduce their blood pressure without the need for medication. Increase your intake of fruits and vegetables, and choose foods that are low in saturated fat and high in fibre, vitamins and minerals. Your doctor or dietitian will be able to help you if you don’t know where to start.
Reduce your salt intake
Many canned, packaged and processed foods contain excessive amounts of salt (sodium chloride) so you should read the labels carefully and choose ‘no added salt’ or ‘low salt’ wherever possible. Remove salt from your recipes wherever you can and limit smoked, cured or processed meat and meat products.
Cut down on alcohol
Limiting your drinking to a moderate amount of alcohol can help lower blood pressure. Current guidelines recommend that healthy men and women should limit their intake to 2 units of alcohol or less per day. A unit of alcohol is roughly equivalent to a standard glass of normal strength beer, a small glass of wine, or a single measure of spirit such as whisky or gin. Both men and women should aim for at least 2 alcohol-free days each week.
Get regular physical activity
Getting regular physical activity will make you feel better and reduce your risk of developing serious or chronic illnesses. Aerobic activities that condition your heart and lungs, such as swimming, walking or cycling, are best.
Start slowly and build up to doing at least 30 minutes of moderate exercise most days. If you don’t have time to do 30 minutes, do what you can: you can do 3 sessions of 10 minutes if this is more convenient.
If you are taking medication, have a history of serious illness, have symptoms such as chest discomfort when you exercise, or have not exercised for a while, check with your doctor before starting a programme. Lifting heavy weights causes increases in blood pressure and isn’t recommended.
Give up smoking
You should also give up smoking. Your doctor will be able to suggest the best quitting strategy for you to follow.
Treatment with medicines
Some people will need to take medicines, in addition to lifestyle measures, to control their blood pressure. The decision to treat high blood pressure with medicines is not based on your blood pressure alone, but on your overall level of cardiovascular risk.
Types of high blood pressure medicines
There are several main types of high blood pressure medicines – also known as antihypertensive medicines. The one you are prescribed will depend on:
- your age;
- any other medical conditions you may have;
- your risk of cardiovascular disease;
- other medicines you may be taking; and
- the medicine’s potential for side effects.
Response to medicines varies among individuals and your doctor may need to try different types and dosages before finding the best one for you.
Blood pressure can sometimes be adequately controlled by one medicine, but often a combination of 2 or 3 medicines is required. The medicines may be prescribed individually (to be taken as separate tablets), or sometimes there is a combination product available (combining different antihypertensives in the one tablet).
Here are some of the types of medicines currently available in Australia.
Angiotensin-converting enzyme inhibitors (ACE inhibitors)
ACE inhibitors block the production of a hormone (angiotensin-2) that narrows blood vessels, allowing the blood vessels to widen and blood to flow more easily, thus lowering blood pressure. ACE inhibitors are also used in heart failure and are useful for preserving kidney function in people with diabetes and kidney disease.
Examples of ACE inhibitors are: captopril (e.g. Capoten, Zedace), enalapril (e.g. Acetec, Auspril, Renitec), fosinopril (e.g. Fosipril, Monace, Monopril), lisinopril (e.g. Fibsol, Prinivil, Zestril, Zinopril), perindopril (e.g. Coversyl, Perindo), quinapril (e.g. Accupril, Acquin, Filpril), ramipril (e.g. Prilace, Ramace, Tritace, Tryzan) and trandolapril (e.g. Dolapril, Gopten, Tranalpha).
There are few side effects with these medicines, the most common being a harmless but persistent dry cough. ACE inhibitors are not suitable for pregnant women.
Angiotensin receptor blockers (ARBs)
The angiotensin receptor blockers (ARBs) are newer than the ACE inhibitors, but work in a similar way. However, they are more selective in their action and may cause fewer side effects, for example they are less likely than the ACE inhibitors to cause cough.
Examples include candesartan (Adesan, Atacand), eprosartan (Teveten), irbesartan (Abisart, Avapro, Karvea), losartan (Cozaar, Cozavan), olmesartan (Olmetec), telmisartan (Micardis, Mizart) and valsartan (Diovan).
Angiotensin receptor blockers are also used in heart failure and to protect kidney function. Like the ACE inhibitors, these medicines should not be taken by pregnant women as they pose a risk to the developing baby.
Calcium channel blockers (also known as calcium antagonists)
Calcium channel blockers work by blocking the flow of calcium in the heart and blood vessels, causing the blood vessels to relax and open up. This lowers the blood pressure. They are often useful for older people and people with asthma or angina or peripheral arterial disease.
Calcium channel blockers include amlodipine (e.g. Nordip, Norvasc, Perivasc), felodipine (Felodil XR, Felodur ER, Fendex ER, Plendil ER), lercanidipine (Zanidip, Zircol), nifedipine (e.g. Adalat Oros, Addos XR, Adefin XL), diltiazem (e.g. Cardizem CD, Vasocardol CD) and verapamil (e.g. Anpec, Cordilox SR, Isoptin SR, Veracaps SR). Many of these medicines are controlled-release preparations, releasing the medicine slowly into the body during the day.
Side effects vary among calcium channel blockers but can include flushing, swelling of the ankles, headache, dizziness, gastrointestinal upset such as constipation (particularly with verapamil) and palpitations; however, generally these medicines are effective and well tolerated.
Diuretics work by helping the kidneys to pass accumulated salt and water. This decreases the amount of fluid in the body and so lowers blood pressure. Diuretics also cause blood vessels to dilate (expand), which lessens the pressure on them.
Thiazide diuretics, for example chlorthalidone (e.g. Hygroton), indapamide (e.g. Dapa-Tabs, Insig, Natrilix SR) and hydrochlorothiazide (Dithiazide), are frequently used but can cause excess potassium to be excreted in the urine, which can be a problem for people with kidney problems.
Potassium-sparing diuretics, such as amiloride (Kaluril) and spironolactone (Aldactone, Spiractin), help the body retain potassium. Various combination products are available in Australia which combine thiazides with potassium-sparing diuretics, for example hydrochlorothiazide plus amiloride (Amizide, Moduretic). Likewise, thiazide diuretics are often co-prescribed with ACE inhibitors (another type of high blood pressure medicine that tends to cause retention of potassium).
Side effects of diuretics can include dizziness, weakness, excessive urination, and more rarely rash and gastrointestinal symptoms. People who have diabetes, liver disease or gout need to be closely monitored by their doctor while taking diuretics as the medicines may aggravate these conditions.
Diuretics are usually prescribed in low doses only, so if you find your diuretic is not reducing your blood pressure, higher doses are unlikely to improve things and your doctor will probably try another type of medicine.
Adrenergic blockers (alpha-blockers and beta-blockers)
These medicines reduce the stimulatory effect of adrenaline and noradrenaline on the heart and blood vessels.
Alpha-blockers, for example prazosin (e.g. Minipress), relax muscles in the walls of the blood vessels and reduce the resistance to blood flow thus allowing blood to flow more easily. They are not usually recommended in the first instance for blood pressure control.
Beta-blockers work by blocking the action of adrenaline and noradrenaline in the heart. Adrenaline speeds up the heart and makes it pump harder, thus increasing blood pressure. Beta-blockers slow the heartbeat, and reduce the force of its contractions so less blood is pumped through the vessels, thus lowering blood pressure.
Examples of beta-blockers include atenolol (e.g. Noten, Tenormin, Tensig), metoprolol (e.g. Betaloc, Lopresor, Metrol, Minax), nebivolol (Nebilet), oxyprenolol (Corbeton), pindolol (e.g. Barbloc, Visken) and propranolol (e.g. Deralin, Inderal). The Heart Foundation recommends that beta-blockers should not be used as a first-option treatment for people with uncomplicated high blood pressure.
Beta-blockers are also used for angina, fast heartbeat, heart failure and prevention of migraine. They are not suitable for people with asthma or certain heart conditions, and because they act on the nervous system they may cause lowered mood or lethargy in some people. They may sometimes cause narrowing of the airways, such as in asthma, and cold hands and feet. Unlike many other high blood pressure medicines, some beta-blockers can be used in pregnancy.
Some beta-blockers, such as labetalol (e.g. Presolol, Trandate) and carvedilol (e.g. Dicarz, Dilasig, Dilatrend) block both beta and alpha receptors.
Centrally-acting antiadrenergic therapy
Like adrenergic blockers, methyldopa (Hydopa), clonidine (Catapres) and moxonidine (Physiotens) act on the nervous system, but more widely than either alpha- or beta-blockers. They act on the part of the brain that controls blood pressure, which results in expansion of the blood vessels, thus lowering blood pressure.
Although very effective, these medicines have more side effects than other antihypertensive medicines, including fatigue, dry mouth, depression, sedation, impotence and headache, so they are generally only considered after other treatments have been tried. Methyldopa can be used to treat pregnant women who can’t take other blood pressure medicines because of the effect on the developing baby.
Vasodilators include hydralazine (Alphapress) and minoxidil (Loniten). They have a strong blood pressure lowering effect and are used for treating high blood pressure that doesn’t respond to other medicines or in emergency situations. They are used generally under the supervision of a specialist.
Follow your doctor’s directions
Some people may wonder why they need to take medicines for a condition that doesn’t have symptoms and doesn’t appear to affect their quality of life. Although taking medication may seem like a chore, it is being prescribed to prevent serious illness or even death.
Always take medicines according to instructions, and do not stop taking them suddenly as this can cause problems. If you have any questions about your medicine, always ask your doctor or pharmacist.