Drugs to treat HTN

Question 1

htn damages

Answer 1

bv in kidney, heart, and brain which leads to end organ damage- MI, stroke, renal failure, death

Question 2

main risk of htn tied to

Answer 2

inc in systolic blood pressure- progressive stiffening of arterial circulation

Question 3

htn stage 1 at

Answer 3

130-139 or 80-89

If 10 yr risk for HD >10%, lifestyle changes and meds

Question 4

htn stage 2 at

Answer 4

> 140 or >90

2 medications of different classes

Question 5

BP=

Answer 5

BP=CO x TPR

Question 6

Primary agents used in tx of htn

Answer 6

• thiazide diuretics
• ACE inhibitors
• ARBs
• Calcium channel blockers

Question 7

Thiazide diuretics

Answer 7

-Inhibit NaCl reabsorption in distal convoluted tubule
-low dose for htn
high dose for CHF
-Hydrochlorothiazide
-chlorthalidone, indapamide, metaolazone
-all are sulfonamides

Question 8

Chlorothalidone

Answer 8

preferred thiazide because of long 1/2 life and research

-more effective as antihtn in AAs and elderly

Question 9

AE of thiazides

Answer 9

• hypokalemic metabolic alkalosis
• hyponatremia, hyperglycemia, hyperlipidemia, hyperuricemia, hypercalcemia (GLUC)

If ED occurs, sildenafil can be added (PDE5 inhibitor)

Question 10

Ang II causes

Answer 10

vasoconstriction by inc peripheral vascular resistance causing inc blood pressure

Question 11

aldosterone causes

Answer 11

inc sodium and water retention–>inc blood pressure

Question 12

ACE inhibitors

Answer 12

• prils
• lower bp by inhibiting ACE which conv ang I to ang II
• decreases peripheral vascular resistance and leads to increased bradykinin (AE of coughing and angioedema)

Question 13

Therapeutics of ACE inhibitors

Answer 13

lower BP w/o compromising blood supply to brain heart or kidneys

• does not cause reflex sympathetic activation
• effective orally for monotherapy

Question 14

ACE inhibitors first choice tx for htn pts with

Answer 14

diabetes, chronic renal disease, or lv hypertrophy

Question 15

ACEI AE

Answer 15

hyperkalemia, cough, angioedema, anaphylaxis

• do not use in comb with ARBs
• contraindicated in pregnancy

Question 16

Angiotensin Receptor Antagonists

Answer 16

• sartan
• more specific than ACE inhibitors because do not affect bradykinin
• more complete inhibition of angiotensin action (other enzymes than ACE can also generate ang II)
• similar AE except coughing (hyperkalemia, reduced renal fxn, contra in pregnancy)

Question 17

Calcium Channel Blockers- cardiac

Answer 17

Verapamil (strongest cardiac effect) and diltiazem act on heart (in between nifedipine and verapamil)

• no reflex tachycardia because they depress SA and AV node
• can cause Myocardial depression- bradycarida- bad in HF

Question 18

Peripheral Calcium channel blockers- Dihydropyridines

Answer 18

• amlodipine, nicardipine, nifedipine (strongest vasodilator), etc.
• strongest vasodilators
• most likely to produce reflex tachycardia

-can cause headache, flushing, dizziness, peripheral edema

Question 19

Calcium channel blockers

Answer 19

-block slow calcium channels will reduce intracellular Ca–> relax arteriolar smooth muscles–> vasodilation and lower BP
-especially used in elderly and AA (along with thiazides)
-

Question 20

Sympatholytic drugs

Answer 20

not recommended for monotherapy because of AE- postural hypotension and sodium retention

Question 21

Cardioselective b blockers

Answer 21

atenolol, betaxolol, bisoprolol, metoprolol

Question 22

cardioselective and vasodilatory b blockers

Answer 22

Nebivolol (NO production)

Question 23

Noncardioselective b blockers

Answer 23

Nadolol, propranolol

Question 24

b blockers- intrinsic sympathomimetic activity

Answer 24

b2 agonists: acebutolol, penbutolol, pindolol

w/ NO production: carteolol

Question 25

b blockers- combined a and b receptors

Answer 25

carvedilol (a1 antagonist, blocks Ca entry) and labetalol (a1 antagonist

Question 26

how do b blockers work

Answer 26

lower BP by blocking b-adrenergic receptors in- heart to reduce CO kidneys to reduce renin secretion CNS to reduce sympathetic vasomotor tone -used with other antihtn to counteract reflex tachycardia caused by vasodilators and increased renin secretion by thiazide and loop diuretics

Question 27

AE of b blockers

Answer 27

- worsen symptom sin pts with reduced myocardial reserve, asthma, peripheral vascular insuff, diabetes (delays recovery of normoglycemia bc inhibits hyperglycemic responses mediated by epinephrine) - decrease exercise tolerance in HF pts - predispose to atherogenesis - GI or CNS minor AE - tachycardia with abrupt cessation

Question 28

Aliskiren

Answer 28

orally active renin inhibitor - dose dep reduction of blood pressure - no generic - avoid in pregnancy, do not combine with ACE or ARB

Question 29

Drugs that block renin secretion

Answer 29

Clonidine- reduce renal sympathetic nerve activity | beta- blocker- block intra and extra renal receptors involved in neural control of renin secretion

Question 30

Doxazosin, prazosin, terazosin

Answer 30

a1 adrenergic antagonist - reduces NE induced vasoconstriction to dilate both arteries and veins - BP falls because of decreased PR - AE: orthostatic hypotension

Question 31

Centrally acting sympatholytic drugs

Answer 31

Clonidine, methyldopa, guanfacine - last line because of significant CNS adverse effects - act in CNS as agonist on presynpatic a2 receptors and reduce peripheral vascular resistance - withdrawal of clonidine may result in hypertensive crisis - methyldopa limited to pregnancy

Question 32

oral direct vasodilators

Answer 32

Hydralazine or minoxidil (K channel opener) | - both selectively dilate arteries (not venous)

Question 33

IV direct vasodilators

Answer 33

sodium nitroprusside (NO, both arteries and veins), diazoxide (activate K channels and hyperpolarize, arteries only), fenoldopam (dopa agonist, selective for arteries), enalaprilat (ACEI), nicardipine (CCB), hydralazine (preeclampsia)

Question 34

direct vasodilators

Answer 34

act on vascular smooth muscles to cause relaxation and reduce vascular resistance--> lower BP -

Question 35

AE of vasodilators

Answer 35

hypotension, headaches, reflex tachycardia - elderly with CAD- hydralazine or minoxidil may induce anginal attacks and MI - hydralazine may cause lupus like syndrome - minoxidil causes hypertrichosis (hair growth)

Question 36

Tx in pregnancy

Answer 36

b- blocker (labetalol) or CCB (nifedipine); methyldopa or hydralazine may also be used