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Back to Cardiovascular Diseases
Hypertension
Updated: September 19, 2006
Treatment
Lifestyle modifications
Lifestyle modifications refer to certain specific recommendations
for changes in habits, diet and exercise. These modifications can
lower the blood pressure as well as improve a patient's response to
blood pressure medications.
Alcohol
People who drink alcohol excessively (over two drinks per day)
have a one and a half to two times increase in the prevalence of
hypertension. The association between alcohol and high blood
pressure is particularly noticeable when the alcohol intake exceeds
5 drinks per day. Moreover, the connection is a dose-related
phenomenon, thus the more alcohol is consumed, the stronger is the
link with hypertension.
Smoking
Although smoking increases the risk of vascular complications in
people who already have hypertension, it is not associated with an
increase in the development of hypertension. Nevertheless, smoking a
cigarette can repeatedly produce an immediate, temporary rise in the
blood pressure of 5 to 10 mm Hg. Steady smokers however, actually may
have a lower blood pressure than nonsmokers. The reason for this is
that the nicotine in the cigarettes causes a decrease in appetite,
which leads to weight loss. This, in turn, lowers the blood
pressure.
Coffee
In one study, the caffeine consumed in 5 cups of coffee daily
caused a mild increase in blood pressure in elderly people who
already had hypertension, but not in those who had normal blood
pressures. What's more, the combination of smoking and drinking
coffee in persons with high blood pressure may increase the blood
pressure more than coffee alone. Limiting caffeine intake and
cigarette smoking in hypertensive individuals, therefore, may be of
some benefit in controlling their high blood pressure.
Salt
The American Heart Association recommends that the consumption of
dietary salt be less than 6 grams of salt per day in the general
population and a lower level (for example, less than 4 grams) for
people with hypertension. To achieve a diet containing less than 4
grams of salt, a person should not add salt to their food or
cooking. Also, the amount of natural salt in the diet can be
reasonably estimated from the labeling information provided with
most purchased foods.
Obesity
Obesity is common among hypertensive patients, and its prevalence
increases with age. In fact, obesity may be what determines the
increased incidence of high blood pressure with age. Obesity can
contribute to hypertension in several possible ways. For one thing,
obesity leads to a greater output of blood because the heart has to
pump out more blood to supply the excess tissue. The increased
cardiac output then can raise the blood pressure. For another thing,
obese hypertensive individuals have a greater resistance in their
peripheral arteries throughout the body. In addition, insulin
resistance and the metabolic syndrome described previously occur
more frequently in the obese. Finally, obesity may be associated
with a tendency for the kidneys to retain salt. Weight loss may help
reverse problems related to obesity while also lowering the blood
pressure. It has been estimated that the blood pressure can be
decreased 0.32 mm Hg for every 1 kg (2.2 pounds) of weight lost down
to ideal body weight for the individual.
Some obese people, especially if they are very obese, have a
syndrome called sleep apnea. This syndrome is characterized by the
periodic interruption of normal breathing during sleep. Sleep apnea
may contribute to the development of hypertension in this subgroup
of obese individuals. This happens because the repeated episodes of
apnea cause hypoxia. The hypoxia then causes the adrenal gland to
release adrenalin and related substances. Finally, the adrenalin and
related substances cause a rise in the blood pressure.
Exercise
A regular exercise program may help lower blood pressure over the
long term. For example, activities such as jogging, bicycle riding,
or swimming for 30 to 45 minutes daily may ultimately lower blood
pressure by as much as 5 to15 mm Hg. Moreover, there appears to be a
relationship between the amount of exercise and the degree to which
the blood pressure is lowered. Thus, the more you exercise (up to a
point), the more you lower the blood pressure. The beneficial
response of the blood pressure to exercise occurs only with aerobic
(vigorous and sustained) exercise programs. Therefore, any exercise
program must be recommended or approved by an individual's
physician.
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Medical Treatment
Goals of treatment
High blood pressure is usually present for many years before its
complications develop. The idea, therefore, is to treat hypertension
early, before it damages critical organs in the body. Accordingly,
increased public awareness and screening programs to detect early,
uncomplicated hypertension are the keys to successful treatment.
Treating high blood pressure successfully early enough 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 (blood
pressure between 120/80 and 139/89)
is appropriate, it is not well established
that treatment with medication of patients with pre-hypertension is
beneficial.
Starting treatment for high blood pressure
Blood pressure that is persistently higher than 140/ 90 mm Hg
usually is treated with lifestyle modifications and medication.
However, if the diastolic pressure remains at a borderline level
(usually under 90 mm Hg, yet persistently above 85), more aggressive
treatment 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, hyperlipidemia, or
diabetes.
Any one of the several classes of medications may be started,
except the alpha-blocker medications. The alpha-blockers 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 myocardial infarction
that weakens the heart muscle (systolic dysfunction). Also,
beta-blockers are sometimes the preferred treatment in hypertensive
patients with a resting tachycardia or an acute heart attack.
Furthermore, patients with hypertension may sometimes have a
co-existing, second medical condition. In such cases, a particular
class of anti-hypertensive medication or combination of drugs may be
chosen as the first line 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 (cardiomyopathies) and certain kidney diseases
where reduction in proteinuria would be beneficial.
In some other situations, certain classes of anti-hypertensive
medications 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 blunt this effect. Furthermore, the non-dihydropyridine
type of calcium channel blockers should not be used in patients with
heart failure or 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 relegated to
second or third line choices for treatment. Clonidine is an
excellent drug but has side effects such as fatigue, sleepiness, and
dry mouth 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.
Treatment with combinations of drugs for high blood pressure
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 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 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 bradycardia. Combining
alpha and beta-blockers may be beneficial for cardiomyopathies and
hypertension. Carvedilol (Coreg) is useful for cardiomyopathies and
labetalol for hypertension patients.
Emergency treatment of high blood pressure
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) and labetalol (Normodyne).
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, dissecting aneurysm (dilation or
widening) of the aorta, stroke, and toxemia of pregnancy.
Treatment during pregnancy
Women with hypertension may become pregnant. These patients have
an increased risk of developing pre-eclampsia or eclampsia (toxemia)
of pregnancy. These conditions usually develop during the last three
months (trimester) of pregnancy. In pre-eclampsia (which can occur
with or without pre-existing hypertension), affected women have
hypertension, proteinuria and edema. In eclampsia 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 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.
Medications used to treat high blood pressure
Angiotensin converting enzyme inhibitors (ACE Inhibitors) and
angiotensin receptor blockers
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 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 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.
As an added benefit, ACE inhibitors may reduce left ventricular
hypertrophy in patients with hypertension. These drugs also appear
to slow the deterioration of kidney function in patients with
hypertension and 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 myocardial
infarction that weakens the heart muscle (systolic dysfunction). ARB
drugs are currently recommended for first line renal protection in
diabetic nephropathy.
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),
captopril (Capoten), lisinopril (Zestril and Prinivil), benazepril (Lotensin),
quinapril (Accupril), perindopril (Aceon), ramipril (Altace),
trandolapril (Mavik), fosinopril (Monopril), and moexipril (Univasc
).
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 on the arteries to which activated angiotensin
must bind to have its effects. As a result, the angiotensin is not
able to work on the artery. 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 proteinuria in certain kidney
diseases and perhaps help strengthen the heart muscle in
cardiomyopathies. Note that both the ACE inhibitors and the ARB
drugs are contraindicated in pregnant women.
Beta-blockers
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, 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 impingement on
the airway causes wheezing, especially in individuals with a
tendency for asthma. 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 tachycardia, angina, or a recent
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),
nadolol (Corgard), betaxolol (Kerlone), acebutolol (Sectral),
pindolol (Visken), and bisoprolol (Zebeta).
Diuretics
Diuretics are among the oldest known medications for treating
hypertension. They work in the tubules of the kidneys to remove salt
from the body. Fluid also may be removed along with the salt.
Diuretics may be used as 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
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. These side
effects include potassium depletion and elevated levels of
triglyceride, uric acid, and glucose in the blood.
Occasionally, when salt retention causing accumulation of water
and edema is a major problem, the more potent, so-called, loop
diuretics may be used in combination with other anti-hypertensive
medications.
The most commonly used diuretics to treat hypertension
include hydrochlorothiazide (Hydrodiuril), 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 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
cardiac arrhythmias. These drugs include amlodipine (Norvasc),
sustained release nifedipine (Procardia XL, Adalat CC), 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
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 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
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 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
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. Minoxidil may
also increase hair growth.
Patient's compliance with medication regimes
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.
Quality of life issues are very important, especially with regard to
compliance with prescribed blood pressure medications. 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. The least expensive medication regimes use
generic 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.
Alternative medicine
Alternative medicine, also called integrative or complementary
medicine, features the use of non-traditional (at least in the
western world) techniques for treatment. For example,
self-relaxation approaches to the therapy of hypertension include
yoga, biofeedback, and meditation. These techniques can, in fact, be
effective in lowering the blood pressure, at least temporarily. Acupuncture has not yet
been established as a standard or proven therapy for hypertension in
the western world.
Certain herbal remedies have blood pressure-lowering components
that may well be effective in treating hypertension. Most herbal
remedies are available as food supplements, and the Food and Drug
Administration (FDA) does not approve them as drugs. Therefore,
herbal treatments for hypertension have not yet been adequately
evaluated in scientifically controlled clinical trials for
effectiveness and safety. In particular, their long-term side
effects are unknown. Furthermore, a major problem with most herbal
treatments is that their contents are not standardized. Moreover,
the ways in which herbal treatments work to lower blood pressure are
not known. Currently, therefore, herbal remedies are usually not
recommended for the treatment of hypertension.
Recent developments
A new class of anti-hypertensive drug, called a vasopeptidase
blocker (inhibitor), has been developed. Uniquely, it works on two
different systems at the same time. It blocks that part of the
renin-angiotensin-aldosterone hormonal system that constricts the
peripheral arteries. It also blocks that part of the body's salt
regulating system that conserves salt. Accordingly, this class of
drug decreases the blood pressure by simultaneously dilating the
peripheral arteries and increasing natriuresis.
One such drug that is currently being studied is called
omapatrilat. In laboratory animals with high blood pressure, this
drug reduces the blood pressure and appears to protect the
end-organs (heart, kidney, and brain) from damage by the high blood
pressure. Moreover, the drug dilates the peripheral arteries, which
increases blood flow to all tissues, and improves cardiac function
in hypertensive patients with heart failure. Not yet approved by the
FDA, omapatrilat is undergoing further testing to evaluate its
effectiveness and safety.
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