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Treatment Of High Blood Pressure Hypertension
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What are the Basic Drugs for treating Hypertension? This section of our site is useful for Doctors as well as for patients.
Treatment of High Blood Pressure | Hypertension You should always Keep in mind
that high blood pressure is usually present for many years before its complications develop. The
idea, therefore, is to treat hypertension early, before it damages important organs in the body.
Accordingly, increased public awareness and screening programs to detect early, uncomplicated
hypertension are the keys to successful treatment of high blood pressure. By treating high blood
pressure successfully early enough, you can significantly decrease the risk of stroke, heart
attack, and kidney failure. The goal for patients with combined systolic and diastolic hypertension is to
attain a blood pressure of 140/85 mm Hg. Bringing the blood pressure down even lower, as mentioned
earlier, may be desirable in African American patients, and patients with diabetes or chronic
kidney disease. Although life style changes in pre-hypertensive patients is appropriate, it is not
well established that treatment with medication of patients with pre-hypertension is
beneficial.
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Points to consider while Starting treatment for high
blood pressure
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Blood pressure that is persistently higher than 140/ 90 mm Hg usually is treated
with lifestyle modifications and medication. If the diastolic pressure remains at a borderline
level (usually under 90 mm Hg, yet persistently above 85), however, more aggressive treatment also
may be started in certain circumstances. These circumstances include borderline diastolic pressures
in association with end-organ damage, systolic hypertension, or factors that increase the risk of
cardiovascular disease, such as age over 65 years, African American decent, smoking, hyperlipemia
(elevated blood fats), or diabetes. Any one of the several classes of medications may be started, except the
alpha-blocker medications. The alpha-blockers drugs are used only in combination with another
anti-hypertensive medication in specific medical situations. In some particular situations, certain classes of anti-hypertensive drugs are
preferable to others as the first line (choice) drugs. For example, Angiotensin converting enzyme
(ACE) inhibitors or angiotensin receptor blocking (ARB) drugs are the drugs of choice in patients
with heart failure, chronic kidney failure (in diabetics or non-diabetics), or heart attack
(myocardial infarction) that weakens the heart muscle (systolic dysfunction), as these have
remodeling effect on heart muscles. Also, beta-blockers are sometimes the preferred treatment in
hypertensive patients with a resting tachycardia (racing heart beat when resting) or an acute
(rapid onset, current) heart attack. Treatment of High Blood Pressure | Hypertension Furthermore, patients with hypertension may sometimes have a co-existing, second
medical disease. In such cases, a particular class of anti-hypertensive medication or combination
of drugs may be chosen as the first line (initial) approach. The idea in these cases is to control
the hypertension while also benefiting the second condition. For example, beta-blockers may treat
chronic anxiety or migraine headache as well as the hypertension. Also, the combination of an ACE
inhibitor and an ARB drug can be used to treat certain diseases of the heart muscle (called
cardiomyopathies) and certain kidney diseases where reduction in proteinuria would be
beneficial. In some other situations, certain classes of anti-hypertensive medications
should not be used (are contraindicated). Dihydropyridine calcium channel blockers used alone may
cause problems for patients with chronic renal disease by tending to increase proteinuria. However,
an ACE inhibitor will decease this effect. Furthermore, the non-dihydropyridine type of calcium
channel blockers(Verapamil, Dilteazam) should not be used in patients with heart failure or certain
abnormal heart rates or rhythms (arrhythmias). On the other hand, these drugs may be beneficial in
treating certain other arrhythmias. Also, some drugs, such as minoxidil, since it is so powerful,
usually are reserved for second or third line choices for treatment. Clonidine is an
excellent drug but has side effects such as fatigue, sleepiness, and dry month that make it a
second or third line choice. That is, it is used only after all of the first and second line drugs
have been tried without success.
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Treatment with combinations
of drugs for high blood pressure
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Most of the times, Doctors have to use combination therapy of Drugs. The use of
combination drug therapy for hypertension is not uncommon. At times, using smaller amounts of one
or more agents in combination can minimize side effects while maximizing the anti-hypertensive
effect. For example, diuretics, which also can be used alone, are more often used in a low dose in
combination with another class of anti-hypertensive medications. In this way, the diuretic has
fewer side effects while it improves the blood pressure-lowering effect of the other drug.
Diuretics also are added to other anti-hypertensive medications when a patient with hypertension
also has fluid retention and swelling (edema). The ACE inhibitors or angiotensin receptor blockers may be useful in combination
with most other anti-hypertensive medications. ACE inhibitors and angiotensin receptor blockers
ARBs have additive effects in treating patients with cardiomyopathies and proteinuria.
Another useful combination is that of a beta-blocker with an alpha-blocker in patients with high
blood pressure and enlargement of the prostate gland in order to treat both conditions
simultaneously. Caution is necessary, however, when combining two drugs that both lower the heart
rate. For example, adding a beta-blocker to a non-dihydropyridine calcium channel blocker (e.g.,
diltiazem or verapamil) warrants caution. Patients receiving a combination of these two classes of
drugs need to be monitored carefully to avoid an excessively slow heart rate (bradycardia).
Combining alpha and beta-blockers may be beneficial for cardiomyopathies and hypertension.
Carvedilol (Coreg) is useful for cardiomyopathies and labetalol for hypertension patients.
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Emergency treatment of high blood pressure
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Treatment of High Blood Pressure | Hypertension In a hospital setting,
injectable drugs may be used for the emergency treatment of hypertension. The most commonly used
agents in this situation are sodium nitroprusside (Nipride, Isoket) and labetalol (Normodyne). As
already mentioned, emergency medical therapy may be needed for patients with severe (malignant)
hypertension. In addition, emergency treatment of hypertension may be necessary in patients with
short duration (acute) congestive heart failure LVF, dissecting aneurysm (dilation or widening) of
the aorta, stroke, and toxemia of pregnancy (see below). In emergency, sublingual medication with
capotopril ACE inhibitor, or sublingual drops of Nefedipine are also used.
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Treatment during
pregnancy
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Women with hypertension may become pregnant. These patients have an increased
risk of developing preeclampsia or eclampsia (toxemia) of pregnancy. These conditions usually
develop during the last three months (trimester) of pregnancy. In preeclampsia, which can occur
with or without pre-existing hypertension, affected women have 3 things, hypertension, protein loss
in the urine (proteinuria), and swelling (edema). In eclampsia (toxemia), convulsions also occur
and the hypertension may require prompt treatment. The foremost goal of treating the high blood
pressure in toxemia is to keep the diastolic pressure below 105 mm Hg in order to prevent a brain
hemorrhage in the mother. Hypertension that develops before the 20th week of pregnancy almost always is
due to pre-existing hypertension and not toxemia. High blood pressure that occurs only during
pregnancy, called gestational hypertension, may start late in the pregnancy. These women, however,
do not have proteinuria, edema, or convulsions. Furthermore, gestational hypertension appears to
have no ill effects on the mother or the fetus. This form of hypertension resolves shortly after
delivery, although it may recur with subsequent pregnancies. The use of medications for hypertension during pregnancy is controversial. The
key question is, "At what level should the blood pressure be maintained?" For one thing, the risk
of untreated mild to moderate hypertension to the fetus or mother during the relatively brief
period of pregnancy probably is not very large. Furthermore, lowering the blood pressure too much
can interfere with the flow of blood to the placenta and thereby impair fetal growth. So, some sort
of a compromise must be met. Accordingly, not all mild or moderate hypertension during pregnancy
needs to be treated with medication. If it is treated, however, the blood pressure should be
reduced slowly and not to very low levels, perhaps not below 140/80. The anti-hypertensive agents used during pregnancy need to be safe for normal
fetal development. The beta-blockers, hydralazine (an old vasodilator), labetalol, alpha methyldopa
(Aldomet), and more recently, the calcium channel blockers have been advocated as suitable
medications for hypertension during pregnancy. Certain other anti-hypertensive medications,
however, are not recommended (they are contraindicated) during pregnancy. These include the ACE
inhibitors, the ARB drugs, and probably the diuretics. ACE inhibitors may aggravate a diminished
blood supply to the uterus (uterine ischemia) and cause kidney dysfunction in the fetus. The ARB
drugs may even lead to death of the fetus. Diuretics can cause depletion of the blood volume and so
impair placental blood flow and fetal growth
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Which medications are used to treat high blood
pressure?
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Angiotensin converting enzyme inhibitors
(ACE Inhibitors) and angiotensin receptor blockers Treatment of High Blood Pressure | Hypertension The angiotensin converting
enzyme (ACE) inhibitors and the angiotensin receptor blocker (ARB) drugs both affect the
renin-angiotensin hormonal system, which, as mentioned previously, helps regulate the blood
pressure. The ACE inhibitors work by blocking (inhibiting) an enzyme that converts the inactive
form of angiotensin in the blood to its active form. The active form of angiotensin constricts or
narrows the arteries, but the inactive form cannot. With an ACE inhibitor as a single drug
treatment (monotherapy), 50 to 60 percent of Caucasians usually achieve good blood pressure
control. African American patients may also respond, but they require higher doses and frequently
do best when an ACE inhibitor is combined with a diuretic. (Diuretics are discussed below.) As an added benefit, ACE inhibitors may reduce an enlarged heart (left
ventricular hypertrophy) in patients with hypertension. These drugs also appear to slow the
deterioration of kidney function in patients with hypertension and protein in the urine
(proteinuria). Moreover, they have been particularly useful in slowing the progression of kidney
dysfunction in hypertensive patients with kidney disease resulting from Type 1 diabetes
(insulin-dependent). Accordingly, ACE inhibitors usually are the first line drugs of choice to
treat high blood pressure in cases that also involve congestive heart failure, chronic kidney
failure in both diabetics and non-diabetics, and heart attack (myocardial infarction) that weakens
the heart muscle (systolic dysfunction). ARB drugs are currently recommended for first line renal
protection in diabetic nephropathy (kidney disease). Patients who are treated with ACE inhibitors who also have kidney disease should
be monitored for further deterioration in kidney function and high serum potassium. In fact, these
drugs may be used to reduce the loss of potassium in people who are being treated with diuretics
that tend to cause patients to lose potassium. ACE inhibitors have few side effects. One bothersome
side effect, however, is a chronic cough. The ACE inhibitors include enalapril (Vasotec, Renitec,
Zepres), captopril (Capoten), lisinopril (Zestril and Prinivil, Lame), benazepril (Lotensin),
quinapril (Accupril), perindopril (Aceon), ramipril (Altace), trandolapril (Mavik), fosinopril
(Monopril), and moexipril (Univasc ). Usually we prefer Monopril for hypertension in kidney failure patients. For patients who develop a chronic cough on an ACE inhibitor, an ARB drug is a
good substitute. ARB drugs work by blocking the angiotensin receptor (binder) on the arteries to
which activated angiotensin 11 must bind to have its effects. As a result, the angiotensin is not
able to work on the artery. (angiotensin is a hormone that constricts the arteries.) The ARB drugs
appear to have many of the same advantages as the ACE inhibitors but without the associated cough.
Accordingly, they are also suitable as first line agents to treat hypertension. ARB drugs include
losartan (Cozaar), irbesartan (Avapro), valsartan (Diovan), candesartan (Atacand), olmesartan
(Benicar), telmisartan (Micardis), and eprosartan (Teveten). In patients who have hypertension in addition to certain second diseases, a
combination of an ACE inhibitor and an ARB drug may be effective in controlling the hypertension
and also benefiting the second disease. For example, while treating hypertension, this combination
of drugs can reduce the loss of protein in the urine (proteinuria) in certain kidney diseases and
perhaps help strengthen the heart muscle in certain diseases of the heart muscle
(cardiomyopathies). Note that both the ACE inhibitors and the ARB drugs are not to be used (are
contraindicated) in pregnant women. Beta-blockers Treatment of High Blood Pressure | Hypertension The sympathetic nervous system
is a part of the nervous system that helps to regulate certain involuntary (autonomic) functions in
the body such as the function of the heart and blood vessels. The nerves of the sympathetic nervous
system extend throughout the body and exert their effects by releasing chemicals that travel to
nearby cells in the body, for example, muscle cells. The released chemicals bind to receptors
(molecules) on the surface of the nearby cells and stimulate or inhibit the function of the cells.
In the heart and blood vessels, the receptors for the sympathetic nervous system that are most
important are the beta receptors. When stimulated, beta-receptors in the heart increase the heart
rate and the strength of heart contractions (pumping action). Beta-blocking drugs acting on the
heart on these Beta receptors, therefore, slow the heart rate and reduce the force of the heart’s
contraction. Stimulation of beta-receptors in the smooth muscle of the peripheral arteries
and in the airways of the lung causes these muscles to relax. Accordingly, beta-blockers cause
contraction of the smooth muscle of the peripheral arteries and thereby decrease the blood flow to
the tissues throughout the body. As a result, the patient may experience, for example, coolness in
the hands and feet. Likewise, in response to the beta-blockers, the airways are squeezed
(constricted) by the contracting smooth muscle. This squeezing (impingement) on the airway causes
wheezing, especially in individuals with a tendency for asthma. So remember, Beta Blockers are
contracindicated in Asthametic patients. In short, beta-blockers reduce both the force of the
heart's pumping action and the blood pressure that the heart generates in the arteries. Beta-blockers remain useful medications in treating hypertension, especially in
patients with a fast heartbeat while resting (tachycardia), cardiac chest pain (angina), or a
recent heart attack (myocardial infarction). For example, beta-blockers appear to improve long-term
survival when given to patients who have had a heart attack. Whether beta-blockers can prevent
heart problems (are cardio-protective) in patients with hypertension any more than other
anti-hypertensive medications, however, is uncertain. Beta-blockers may be considered for treatment
of hypertension because they also may treat co-existing medical problems. For example,
beta-blockers can help treat chronic anxiety or migraine headaches in people with hypertension. The
common side effects of these drugs include depression, fatigue, nightmares, sexual impotence in
males, and increased wheezing in people with asthma. The beta-blockers include atenolol (Tenormin),
propranolol (Inderal), metoprolol (Toprol, Mepressor, Merol), nadolol (Corgard), betaxolol
(Kerlone), acebutolol (Sectral), pindolol (Visken), and bisoprolol (Zebeta). Diuretics Treatment of High Blood Pressure | Hypertension Diuretics are among the oldest
known medications for treating hypertension. They work in the tiny tubes (tubules) of the kidneys
to remove salt from the body. Water (fluid) also may be removed along with the salt. Diuretics may
be used as single drug treatment (monotherapy) for hypertension. More frequently, however, low
doses of diuretics are used in combination with other anti-hypertensive medications to enhance the
effect of the other medications. The diuretic hydrochlorothiazide (Hydrodiuril) works in the far end (distal)
part of the kidney tubules to increase the amount of salt that is removed from the body in the
urine. In a low dose of 12.5 to 25 mg per day, this diuretic may improve the blood
pressure-lowering effects of other anti-hypertensive drugs. The idea is to treat the hypertension
without causing the adverse effects that are sometimes seen with the higher doses of
hydrochlorothiazide. There side effects include potassium depletion and elevated levels of
triglyceride (fat), uric acid, and glucose (sugar) in the blood. Occasionally, when salt retention causing accumulation of water and swelling
(edema) is a major problem, the more potent, so-called, loop diuretics may be used in combination
with other anti-hypertensive medications. (The loop diuretics are so called because they work in
the loop segment of the kidney tubules to eliminate salt.) The most commonly used diuretics to
treat hypertension include hydrochlorothiazide (Hydrodiuril, Diuza), the loop diuretics furosemide
(Lasix) and torsemide (Demadex), the combination of triamterene and hydrochlorothiazide (Dyazide),
and metolazone (Zaroxolyn). For those individuals who are allergic to sulfa drugs, ethacrynic acid,
a loop diuretic, is a good option. Note that diuretics probably should not be used in pregnant
women. Calcium channel blockers (CCBs) Calcium channel blockers inhibit the movement of calcium into the muscle cells
of the heart and arteries. The calcium is needed for these muscles to contract. These drugs,
therefore, lower blood pressure by decreasing the force of the heart's pumping action (cardiac
contraction) and relaxing the muscle cells in the walls of the arteries. Three major types of calcium channel blockers are used. One type is the
dihydropyridines, which do not slow the heart rate or cause other abnormal heart rates or rhythms
(cardiac arrhythmias). These drugs include amlodipine (Norvasc), sustained release nifedipine
(Procardia XL, Adalat CC, Adalet retard), felodipine (Plendil), and nisoldipine (Sular). The other two types of calcium channel blockers are referred to as the
non-dihydropyridine agents. One type is verapamil (Calan, Covera, Isoptin, Verelan) and the other
is diltiazem (Cardizem, Tiazac, Dilacor, and Diltia). Both the dihydropyridines and the
non-dihydropyridines are very useful when used alone or in combination with other anti-hypertensive
agents. The non-dihydropyridines, however, are not recommended (contraindicated) in congestive
heart failure or with certain arrhythmias. Sometimes, however, these same dihydropyridines are
useful in preventing certain other arrhythmias. Many of the calcium channel blockers come in a short-acting form and a
long-acting (sustained release) form. The short-acting forms of the calcium channel blockers,
however, may have adverse long-term consequences, such as strokes or heart attacks. These effects
are presumably due to the wide fluctuations in the blood pressure and heart rate that occur during
treatment. The fluctuations result from the rapid onset and short duration of the short-acting
compounds. When the calcium channel blockers are used in sustained release preparations, however,
less fluctuation occurs. Accordingly, the sustained release forms of calcium channel blockers are
probably safer for long-term use. The main side effects of these drugs include constipation,
swelling (edema), and a slow heart rate (only with the non-dihydropyridine types). Alpha-blockers Treatment of High Blood Pressure | Hypertension Alpha-blockers lower blood
pressure by blocking alpha-receptors in the smooth muscle of peripheral arteries throughout the
tissues of the body. The alpha-receptors are part of the sympathetic nervous system, as are the
beta-receptors. The alpha-receptors, however, serve to narrow (constrict) the peripheral arteries.
Accordingly, the alpha-blockers cause the peripheral arteries to widen (dilate) and thereby lower
the blood pressure. Recent evidence, however, suggests that using alpha-blockers alone as a first
line drug choice for hypertension may actually increase the risk of heart-related problems, such as
heart attacks or strokes. Alpha-blockers, therefore, should not be used as an initial drug choice
for the treatment of high blood pressure. Examples of alpha-blockers include terazosin (Hytrin) and
doxazosin (Cardura) . Alpha-blockers are particularly useful in patients with enlargement of the
prostate gland (which usually occurs in older men) because these drugs reduce the problems
associated with urinating. Alpha-blockers alone, however, have a relatively small blood
pressure-lowering effect. Accordingly, when hypertension coexists with prostatic enlargement,
another anti-hypertensive medication should be used together with an alpha-blocker. For example,
tamsulosin (Flomax) or alfuzosin (Uroxatral) are alpha-blockers that work well in combination with
other anti-hypertensive medications. Clonidine Clonidine (Catapres) is an antihypertensive drug that works centrally. That is,
it works in a control center for the sympathetic nervous system in the brain. The drug is referred
to as a central alpha agonist because it stimulates alpha-receptors in the brain. The result of
this central stimulation, however, is to decrease the sympathetic nervous system outflow and to
decrease the stiffness (resistance) of the peripheral arteries. Clonidine lowers the blood
pressure, therefore, by relaxing (dilating or widening) the peripheral arteries throughout the
body. This drug is useful as a second or third line drug choice for lowering blood pressure when
other anti-hypertensive medications have failed. It also may be useful on an as-needed basis to
control or smooth out fluctuations in the blood pressure. This drug tends to cause dryness of the
mouth and fatigue so that some patients do not tolerate it. Clonidine comes in an oral form or as a
sustained release skin patch. Minoxidil Treatment of High Blood Pressure | Hypertension Minoxidil is the most potent of
the drugs that lower blood pressure by dilating the peripheral arteries. This drug, however, does
not work through the peripheral sympathetic nervous system, as do the alpha and beta-blocker drugs,
or through the control center in the brain, as does clonidine. Rather, it is a muscle relaxant that
works directly on the smooth muscle of the peripheral arteries throughout the body. Minoxidil is
used for patients who have not responded to any other medications. It must be combined with a
beta-blocker or clonidine to prevent an increase in the heart rate and with a diuretic to prevent
retention of fluid (swelling). Minoxidil may also increase hair growth. So Minoxidil is also used
for baldness.
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What about the patient's
compliance with medication regimes?
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When uncomplicated hypertension has not caused symptoms, as often happens, some
patients tend to forget about their medications. Patients also tend to fail to take their
medications as prescribed (non-compliance or non-adherence) if they are causing side effects.
Remember that quality of life issues are very important, especially with regard to compliance with
prescribed blood pressure medications. Thus, certain anti-hypertensive medications may cause such
side effects as fatigue and sexual impotence. These side effects understandably can have profound
effects on the patient's quality of life and compliance with treatment. Likewise, more resistant
cases of hypertension that require more medication may cause more adverse effects, and, therefore,
less compliance. In dosing schedules that require taking medication 2 to 4 times a day (split
dose), some patients will remember to take their medicine only some of the times. In contrast,
medications that can be given once daily tend to be remembered more regularly. Expensive blood pressure medications, especially if insurance does not cover the
costs, may also reduce compliance. The reason for this is that people attempt to save money by
skipping doses of the prescribed medication. Remember that the least expensive medication regimes
use generic (not brand name) drugs, such as are readily available for some of the diuretics and
beta-blockers. Reduced costs of medication may also be achieved by lifestyle changes such as losing
weight, reducing dietary sodium, decreasing consumption of alcohol, and exercising regularly. If
these changes in lifestyle are effective, the patient may require less medication. For further
information, please read the natural treatment of hypertension.
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