Encyclopedia of Health and Medicine

medications to treat cardiovascular disease 81
headache. Loop diuretics also can damage the
structures of the inner EAR, resulting in temporary
or permanent HEARING LOSS.
COMMON LOOP DIURETICS
bumetanide (Bumex)
ethacrynic acid (Edecrin)
furosemide (Lasix, Myrosemide) torsemide (Demadex)
Potassium-sparing diuretics These drugs prevent
the kidneys from withholding sodium, the
electrolyte most responsible for fluid retention,
though allow the kidneys to pull potassium from
the blood. They are the least potent of the diuretic
drugs, acting on other sites in the glomeruli that
regulate specifically sodium reabsorption. The two
potassium-sparing diuretics available in the United
States are amiloride (Midamor) and triamterene
(Dyrenium). The aldosterone blockers eplerenone
and spironolactone are also potassium sparing.
Thiazide diuretics The thiazide diuretics are
the first line of therapy for hypertension and heart
failure, often in combination with other cardiovascular
medications. Their actions are more moderate
than those of the loop diuretics, creating less of
a risk for potassium depletion though such risk
still exists. There are numerous thiazide diuretics,
only some of which doctors prescribe for cardiovascular
conditions. Because thiazides are so commonly
used with other medications, there are also
numerous formulations that incorporate a thiazide
with another cardiovascular drug.
COMMON THIAZIDE DIURETICS
chlorothiazide (Diuril, Diurigen)
chlorthalidone (Hygroton, Thalitone)
hydrochlorothiazide (Ezide, Esidrix, HCTZ,
Hydro-Chlor, Hydro-D, HydroDIURIL, Microzide, Oretic)
hydroflumethiazide (Diucardin, Saluron)
methyclothiazide (Aquatensen, Enduron)
metolazone (Diulo, Mykrox, Zaroxolyn)
polythiazide (Renese)
quinethazone (Hydromox)
trichlormethiazide (Metahydrin, Naqua, Trichlorex)
Inotropics
Inotropic drugs draw more calcium into myocardial
cells, intensifying their contractility (the force
with which they contract) and increasing the
heart’s effectiveness while decreasing the effort
required. Inotropic drugs administered intravenously
during cardiovascular emergency
include dopamine, dobutamine, and milrinone;
these drugs give the heart a “jolt” to help it pull
out of CARDIAC ARREST. Digoxin (short-acting) and
digitoxin (long-acting), forms of digitalis, are the
inotropic medications for chronic or extended oral
therapy. Though once the cornerstone of therapy
for heart failure (notably congestive heart failure),
digoxin has a very narrow therapeutic index,
making toxicity a worrisome concern. Digoxin
interacts with numerous other medications
including those that more effectively treat heart
failure, and the heart becomes dependent on it.
Digoxin also acts to slow the number of electrical
impulses that cross the ATRIOVENTRICULAR (AV)
NODE, slowing and regulating the contractions of
the myocardial cells. Cardiologists may prescribe
digoxin to treat atrial fibrillation. The most common
brand name digoxin product in the United
States is Lanoxin.
Lipid-Lowering
Lipid-lowering medications reduce blood levels of
cholesterol and triglycerides, lowering the risk for
atherosclerosis and its related conditions CAD and
PVD. There are four classifications of lipid-lowering
medications, each with a different mechanism
of action: BILE acid sequestrants, fibrates, statins,
and selective cholesterol absorption inhibitors. As
well, niacin acts to block cholesterol and lipoprotein
synthesis in the LIVER.
Bile acid sequestrants The bile acid sequestrants
were the first cholesterol-lowering medications to
become available. They work by binding with bile
in the gastrointestinal tract, preventing the body
from reabsorbing cholesterol the bile contains. Bile
acid sequestrants can reduce low-density lipoprotein
cholesterol (LDL-C) by about 20 percent and
total cholesterol by 5 to 10 percent. These medications
come as powders to mix with juices or foods
such as applesauce, and commonly cause gastrointestinal
distress. Bile acid sequestrants interact with
numerous medications, including beta blockers,
diuretics, and the anticoagulant warfarin.
COMMON BILE ACID SEQUESTRANTS
cholestyramine (Questran, colesevelam (WelChol)
Prevalite)
colestipol (Colestid)