excretion. When aldosterone is blocked, sodium is excreted along with water
and potassium is retained. These drugs cause little change in cardiac output or
heart rate and lower peripheral resistance. They can be used in patients with ele-
vated serum renin levels.
They are used primarily to treat hypertension; some of the agents are also
effective in treating heart failure. Examples of these drugs include benazepril
(Lotensin), captopril (Capoten), enalapril maleate (Vasotec), enalaprilat (Vasotec
IV), lisinopril (Prinivil, Zestril), and ramipril (Altace).
Losartan (Cozaar), valsartan (Diovan), and irbesartan (Avapro) are
Angiotensin II blockers that block angiotension II at the receptor site. ACE
inhibitors and angiotensin II receptor antagonists are less effective for treating
hypertension in African-American persons. They both may cause angioedema.
Angioedema is very similar to urticaria, with which it often coexists and over-
laps. The swellings occurs especially in the lips and other parts of the mouth
and throat, the eyelids, the genitals, and the hands and feet. Angioedema is
life-threatening if swelling in the mouth or throat makes it difficult to breathe.
Less often the sheer amount of swelling means that so much fluid has moved out
of the blood circulation that blood pressure drops dangerously.
CLALCIUM CHANNEL BLOCKERS
As discussed previously in this chapter, calcium channel blockers decrease
calcium levels and promote vasodilation. Calcium channel blockers include
verapamil (Calan), diltiazem (Cardiazem), nifedipine (Procardia), amlodipine
(Norvasc), felodipine (Plendil), nicardipine HCl (Cardene), and nisoldipine
(Sular, Nisocor).
Calcium channel blockers can be combined with ACE inhibitors. Such
combinations include benazepril with amlodipine (Lotrel), enalapril with
diltiazem (Teczem), enalapril with felodipine (Lexxel), and trandolapril
with verapamil (Tarka).
A list of ACE inhibitor drugs in the Appendix. Detailed tables show doses,
recommendations, expectations, side effects, contraindications, and more; avail-
able on the book’s Web site (see URL in Appendix).
DIURETICS
Diuretics lower blood pressure and decrease peripheral and pulmonary edema in
congestive heart failure and renal or liver disorders by inhibiting sodium and water
reabsorption from the kidney tubules resulting in increased urine flow (diuresis).
CHAPTER 19 Cardiac Circulatory Medications^359