Antihypertensive agents

Question 1

What are causes of secondary HTN?

Answer 1

1. Renal artery constriction
2. coarctation of the aorta
3. pheochromocytoma
4. Cushing’s disease
5. primary aldosteronism

Question 2

Adverse effects of diuretics

Answer 2

1. potassium loss
2. depletion of magnesium
3. impaired glucose tolerance
4. increased serum lipids
5. increased uric acid (can precipitate gout)

Question 3

General guidelines for ACE inhibitor use in HTN

Answer 3

reduces bp by < 10 mm Hg and this is inadequate for Stage 2 HTN

long-term benefits in reducing renal disease in diabetics and reduction of heart failure makes ACE inhibitors useful

Question 4

How does angiotensin II contribute to HTN?

Answer 4

1. directly constricts resistance vessels
2. is converted in the adrenal gland to ANG III -> both ANG II and III stimulate synthesis of aldosterone which increases sodium reabsorption

Question 5

How does renal stenosis cause HTN?

Answer 5

plaque forms in the aorta at the origin of the renal artery, decreasing perfusion. Reduced blood flow causes kidney to release renin in response.

Look for abdominal bruit or unexplained hypokalemia. Hypokalemia is caused by elevated aldosterone which promotes excretion of potassium (absorb sodium, excrete potassium)

Question 6

What drug is most comonly used to treat hypertensive emergencies?

Answer 6

sodium nitroprusside

Give with furosemide to prevent volume expansion with powerful vasodilation

dilates both arteries and veins, so get decreased PVR and venous return

CO increases due to decreased afterload

Adverse: cyanide accumulation, metabolic acidosis, arrhythmias, excessive hypotension

Question 7

drug that blocks VMAT and results in depletion of NE, dopamine, and serotonin in central and peripheral neurons

Adverse: sedation, depression, Parkinsonism symptoms

Answer 7

reserpine

Question 8

nonselective beta blockers with long half-lives

not metabolized

excreted in urine unchanged

Answer 8

nadolol

carteolol

betaxolol

bisoprolol

Question 9

beta blockers that can be used for HTN in patients with bradyarrhythmias or PVD, since they are partial agonists with some sympathomimetic activity

Answer 9

pindolol

acebutolol

penbutolol

Question 10

unique feature of esmolol

Answer 10

short half-life

used for intraoperative and postop HTN associated with tachycardia

Question 11

blocks alpha-1 receptors in arterioles and venules without blocking alpha-2 (less tachycardia)

give with diuretic, because can cause water and sodium retention

Answer 11

prazosin

terazosin

doxazosin

Question 12

used for long-term maintenance of HTN

dilates arterioles not veins

no orthostatic hypotension or sexual dysfunction because it does not affect the baroreceptor reflex

use in combo with nitrates in African American patients for HTN and heart failure

avidly binds to vascular tissue and is able to persist longer despite significant first pass effect

Answer 12

hydralazine

Question 13

dilates arterioles and not veins

opens potassium channels in smooth muscle membranes, stabilizing the resting membrane potential and decreasing contraction

must be given with a loop diuretic and beta blocker

use when hydralazine is not effective

Answer 13

minoxidil

Question 14

arteriolar dilator used for hypertensive emergencies

inhibits insulin release from the pancreas in treatment of hypoglycemia from insulinoma

Answer 14

diazoxide

Question 15

dilates peripheral arterioles

used for hypertensive emergencies & postop HTN

D1 agonist -> dilates peripheral arteries and natriuresis

Do not use in glaucoma

Answer 15

fenoldopam

Question 16

Non dihydropyradine calcium channel blockers with cardiac depressant effects

Answer 16

verapamil

diltiazem

Question 17

dihydropyridine calcium channel blockers

decrease calcium influx into arterial smooth muscle cells

Answer 17

amlodopine

felodipine

isradipine

nicardipine

nifedipine

nisoldipine

clevidipine

Question 18

competitive inhibitors of ANG II at its receptors providing more selective blockade of angiotensin effects than ACE inhibitors

Unlike ACE inhibitors, these do not have a bradykinin mechanism

cough and angioedema less common

Answer 18

losartan

valsartan

candesartan

eprosartan

irbesartan

telmisartan

olmesartan

Question 19

renin antagonist

sits on the angiotensinogen proteolytic site

contraindicated in pregnancy

Answer 19

aliskiren

Question 20

aldosterone receptor inhibitors

potassium sparing diuretics by promoting sodium excretion in the distal nephron

Answer 20

spironolactone

eplerenone

Question 21

ACE inhibitors

decreases ANG II

increases concentration of circulating bradykinin (vasodilator)

adverse: dry cough with wheeze, acute renal failure, severe hypotension in patients who are hypovolemic from diuretics, salt restriction or GI loss of fluid, hyperkalemia

DO NOT use in 2nd or 3rd trimesters of pregnancy because causes fetal renal failure & hypotension

Answer 21

captopril

lisinopril

enalapril

benazepril

fosinopril

moexipril

perindopril

quinapril

ramipril

trandolapril

Question 22

nonselective endothelin receptor blocker

Adverse: teratogen, headache, increased HR, facial flushing, facial edema, nausea, vomiting, fatal hepatotoxicity

Answer 22

bosentan

Question 23

selective ETA receptor antagonists

Answer 23

ambrisentan

sitaxsentan